diff --git a/codeql-workspace.yml b/codeql-workspace.yml
index a6408dc26ec..c61313163e5 100644
--- a/codeql-workspace.yml
+++ b/codeql-workspace.yml
@@ -3,6 +3,7 @@ provide:
   - "*/ql/lib/qlpack.yml"
   - "*/ql/test*/qlpack.yml"
   - "*/ql/upgrade-tests/qlpack.yml"
+  - "*/ql/downgrade-tests/qlpack.yml"
   - "*/ql/examples/qlpack.yml"
   - "*/ql/consistency-queries/qlpack.yml"
   - "*/ql/automodel/src/qlpack.yml"
diff --git a/rust/ql/downgrade-tests/.gitignore b/rust/ql/downgrade-tests/.gitignore
new file mode 100644
index 00000000000..3b4d77eb40d
--- /dev/null
+++ b/rust/ql/downgrade-tests/.gitignore
@@ -0,0 +1,3 @@
+*.testproj/
+*.actual
+*.log
diff --git a/rust/ql/downgrade-tests/66a489863649185f4a9770f894505803059a1312/.gitignore b/rust/ql/downgrade-tests/66a489863649185f4a9770f894505803059a1312/.gitignore
new file mode 100644
index 00000000000..1abb3d60e26
--- /dev/null
+++ b/rust/ql/downgrade-tests/66a489863649185f4a9770f894505803059a1312/.gitignore
@@ -0,0 +1,5 @@
+*.testproj/
+*.actual
+*.log
+Cargo.toml
+lib.rs
diff --git a/rust/ql/downgrade-tests/66a489863649185f4a9770f894505803059a1312/README.md b/rust/ql/downgrade-tests/66a489863649185f4a9770f894505803059a1312/README.md
new file mode 100644
index 00000000000..3cc35fab477
--- /dev/null
+++ b/rust/ql/downgrade-tests/66a489863649185f4a9770f894505803059a1312/README.md
@@ -0,0 +1,24 @@
+# Downgrade Regression Test for rust-analyzer 0.0.328 -> 0.0.301
+
+This test verifies that the dbscheme downgrade script correctly preserves recoverable data when migrating databases from the new schema back to the old schema.
+
+## Running the test
+
+```bash
+./run-test.sh
+```
+
+This will:
+1. Build the current extractor
+2. Create a database with the new schema from `upgrade_shapes.rs`
+3. Validate the new-schema extraction
+4. Downgrade the database to the old schema
+5. Check out the old commit (491c373e076)
+6. Verify that the recovered old-schema properties still match
+
+## Files
+
+- `new.ql` / `new.expected`: Query for the new schema (validates extraction)
+- `downgraded.ql` / `downgraded.expected`: Query for the downgraded old schema
+- `upgrade_shapes.rs`: Rust source containing test shapes for all affected schema elements
+- `run-test.sh`: Test runner script
diff --git a/rust/ql/upgrade-tests/66a489863649185f4a9770f894505803059a1312/downgraded.expected b/rust/ql/downgrade-tests/66a489863649185f4a9770f894505803059a1312/downgraded.expected
similarity index 87%
rename from rust/ql/upgrade-tests/66a489863649185f4a9770f894505803059a1312/downgraded.expected
rename to rust/ql/downgrade-tests/66a489863649185f4a9770f894505803059a1312/downgraded.expected
index 1df9e112bbe..0616c973cb6 100644
--- a/rust/ql/upgrade-tests/66a489863649185f4a9770f894505803059a1312/downgraded.expected
+++ b/rust/ql/downgrade-tests/66a489863649185f4a9770f894505803059a1312/downgraded.expected
@@ -1,6 +1,6 @@
 formatArgsArgName
-| upgrade_shapes.rs:22:37:22:41 | FormatArgsArg | upgrade_shapes.rs:22:37:22:37 | (no string representation) | upgrade_shapes.rs:22:41:22:41 | 1 | 37 |
-| upgrade_shapes.rs:22:44:22:48 | FormatArgsArg | upgrade_shapes.rs:22:44:22:44 | (no string representation) | upgrade_shapes.rs:22:48:22:48 | 2 | 44 |
+| upgrade_shapes.rs:22:37:22:41 | FormatArgsArg | upgrade_shapes.rs:22:13:22:49 | (no string representation) | upgrade_shapes.rs:22:41:22:41 | 1 | 13 |
+| upgrade_shapes.rs:22:44:22:48 | FormatArgsArg | upgrade_shapes.rs:22:13:22:49 | (no string representation) | upgrade_shapes.rs:22:48:22:48 | 2 | 13 |
 tryBlock
 | upgrade_shapes.rs:21:13:21:21 | { ... } |
 structFieldDefault
diff --git a/rust/ql/upgrade-tests/66a489863649185f4a9770f894505803059a1312/downgraded.ql b/rust/ql/downgrade-tests/66a489863649185f4a9770f894505803059a1312/downgraded.ql
similarity index 100%
rename from rust/ql/upgrade-tests/66a489863649185f4a9770f894505803059a1312/downgraded.ql
rename to rust/ql/downgrade-tests/66a489863649185f4a9770f894505803059a1312/downgraded.ql
diff --git a/rust/ql/downgrade-tests/66a489863649185f4a9770f894505803059a1312/new.expected b/rust/ql/downgrade-tests/66a489863649185f4a9770f894505803059a1312/new.expected
new file mode 100644
index 00000000000..441d08ab3c3
--- /dev/null
+++ b/rust/ql/downgrade-tests/66a489863649185f4a9770f894505803059a1312/new.expected
@@ -0,0 +1,20 @@
+formatArgNamePreserved
+| upgrade_shapes.rs:22:37:22:41 | FormatArgsArg | upgrade_shapes.rs:22:37:22:39 | FormatArgsArgName | upgrade_shapes.rs:22:41:22:41 | 1 | 37 | 1 |
+| upgrade_shapes.rs:22:44:22:48 | FormatArgsArg | upgrade_shapes.rs:22:44:22:46 | FormatArgsArgName | upgrade_shapes.rs:22:48:22:48 | 2 | 44 | 2 |
+tryBlockModifierPreserved
+| upgrade_shapes.rs:21:13:21:21 | { ... } | upgrade_shapes.rs:21:13:21:15 | TryBlockModifier |
+structFieldDefaultPreserved
+| upgrade_shapes.rs:9:5:9:17 | field: u8 | upgrade_shapes.rs:9:17:9:17 | ConstArg | upgrade_shapes.rs:9:17:9:17 | 1 |
+variantDiscriminantPreserved
+| upgrade_shapes.rs:13:5:13:9 | V | upgrade_shapes.rs:13:9:13:9 | ConstArg | upgrade_shapes.rs:13:9:13:9 | 2 |
+pathMetaPreserved
+| upgrade_shapes.rs:4:3:4:11 | PathMeta | path_meta |
+| upgrade_shapes.rs:7:10:7:18 | PathMeta | path_meta |
+keyValueMetaPreserved
+| upgrade_shapes.rs:5:3:5:15 | KeyValueMeta | key_value | upgrade_shapes.rs:5:15:5:15 | 1 |
+tokenTreeMetaPreserved
+| upgrade_shapes.rs:6:3:6:18 | TokenTreeMeta | token_tree | upgrade_shapes.rs:6:13:6:18 | TokenTree |
+unsafeMetaPreserved
+| upgrade_shapes.rs:7:3:7:19 | UnsafeMeta | upgrade_shapes.rs:7:10:7:18 | PathMeta | path_meta |
+traitAliasPreserved
+| upgrade_shapes.rs:16:1:18:12 | trait Alias | upgrade_shapes.rs:16:7:16:11 | Alias | upgrade_shapes.rs:16:18:16:22 | ... | upgrade_shapes.rs:17:1:18:11 | WhereClause |
diff --git a/rust/ql/downgrade-tests/66a489863649185f4a9770f894505803059a1312/new.ql b/rust/ql/downgrade-tests/66a489863649185f4a9770f894505803059a1312/new.ql
new file mode 100644
index 00000000000..bd983a8290c
--- /dev/null
+++ b/rust/ql/downgrade-tests/66a489863649185f4a9770f894505803059a1312/new.ql
@@ -0,0 +1,73 @@
+import codeql.rust.elements
+
+private predicate inUpgradeShapesFile(Locatable loc) {
+  loc.getFile().getBaseName() = "upgrade_shapes.rs"
+}
+
+query predicate formatArgNamePreserved(
+  FormatArgsArg arg, FormatArgsArgName argName, Expr expr, int argNameColumn, string exprText
+) {
+  inUpgradeShapesFile(arg) and
+  argName = arg.getArgName() and
+  expr = arg.getExpr() and
+  argNameColumn = argName.getLocation().getStartColumn() and
+  exprText = expr.toString()
+}
+
+query predicate tryBlockModifierPreserved(BlockExpr block, TryBlockModifier modifier) {
+  inUpgradeShapesFile(block) and
+  modifier = block.getTryBlockModifier() and
+  modifier.isTry() and
+  not modifier.hasTypeRepr()
+}
+
+query predicate structFieldDefaultPreserved(StructField field, ConstArg defaultVal, Expr expr) {
+  inUpgradeShapesFile(field) and
+  defaultVal = field.getDefaultVal() and
+  expr = defaultVal.getExpr()
+}
+
+query predicate variantDiscriminantPreserved(Variant variant, ConstArg constArg, Expr expr) {
+  inUpgradeShapesFile(variant) and
+  constArg = variant.getConstArg() and
+  expr = constArg.getExpr()
+}
+
+query predicate pathMetaPreserved(PathMeta meta, string pathText) {
+  inUpgradeShapesFile(meta) and
+  pathText = meta.getPath().getText() and
+  pathText = "path_meta"
+}
+
+query predicate keyValueMetaPreserved(KeyValueMeta meta, string pathText, Expr expr) {
+  inUpgradeShapesFile(meta) and
+  pathText = meta.getPath().getText() and
+  pathText = "key_value" and
+  expr = meta.getExpr()
+}
+
+query predicate tokenTreeMetaPreserved(TokenTreeMeta meta, string pathText, TokenTree tokenTree) {
+  inUpgradeShapesFile(meta) and
+  pathText = meta.getPath().getText() and
+  pathText = "token_tree" and
+  tokenTree = meta.getTokenTree()
+}
+
+query predicate unsafeMetaPreserved(UnsafeMeta meta, PathMeta inner, string pathText) {
+  inUpgradeShapesFile(meta) and
+  meta.isUnsafe() and
+  inner = meta.getMeta() and
+  pathText = inner.getPath().getText() and
+  pathText = "path_meta"
+}
+
+query predicate traitAliasPreserved(
+  Trait trait, Name name, TypeBoundList bounds, WhereClause whereClause
+) {
+  inUpgradeShapesFile(trait) and
+  name = trait.getName() and
+  name.getText() = "Alias" and
+  bounds = trait.getTypeBoundList() and
+  whereClause = trait.getWhereClause() and
+  not trait.hasAssocItemList()
+}
diff --git a/rust/ql/downgrade-tests/66a489863649185f4a9770f894505803059a1312/run-test.sh b/rust/ql/downgrade-tests/66a489863649185f4a9770f894505803059a1312/run-test.sh
new file mode 100755
index 00000000000..48c78127bc5
--- /dev/null
+++ b/rust/ql/downgrade-tests/66a489863649185f4a9770f894505803059a1312/run-test.sh
@@ -0,0 +1,65 @@
+#!/usr/bin/env bash
+# Manual regression test for the Rust dbscheme downgrade from rust-analyzer 0.0.328 to 0.0.301.
+# See README.md for details.
+
+set -euo pipefail
+
+SCRIPT_DIR="$(cd "$(dirname "${BASH_SOURCE[0]}")" && pwd)"
+REPO_ROOT="$(git rev-parse --show-toplevel)"
+OLD_COMMIT="${OLD_COMMIT:-491c373e076}"  # origin/main at time of this upgrade
+OLD_DBSCHEME="rust/downgrades/109496fd2f20f28a35e50b110859e74882ee80d6/rust.dbscheme"
+
+cd "$REPO_ROOT"
+
+if ! git diff --quiet HEAD || [ -n "$(git ls-files --others --exclude-standard)" ]; then
+    echo "ERROR: Working directory has uncommitted changes." >&2
+    echo "Please commit or stash your changes before running this test." >&2
+    exit 1
+fi
+
+ORIGINAL_REF="$(git rev-parse --abbrev-ref HEAD)"
+if [ "$ORIGINAL_REF" = "HEAD" ]; then
+    ORIGINAL_REF="$(git rev-parse HEAD)"
+fi
+
+restore_ref() {
+    echo "==> Restoring original ref ($ORIGINAL_REF)..."
+    git checkout --quiet "$ORIGINAL_REF"
+}
+trap 'restore_ref' EXIT
+
+echo "==> Building current extractor (this may take a while)..."
+bazel run //rust:install
+
+echo "==> Creating new-schema test database..."
+codeql test run \
+    --search-path . \
+    --keep-databases \
+    "$SCRIPT_DIR/new.ql" "$@"
+
+echo "==> Downgrading dataset to old schema..."
+DATASET_DIR=("$SCRIPT_DIR"/*.testproj/db-rust)
+if [[ ! -d "${DATASET_DIR[0]}" ]]; then
+    echo "ERROR: No testproj found at $SCRIPT_DIR/*.testproj" >&2
+    exit 1
+fi
+codeql dataset upgrade "${DATASET_DIR[0]}" \
+    --allow-downgrades \
+    --search-path rust \
+    --target-dbscheme "$OLD_DBSCHEME"
+
+echo "==> Checking out old commit ($OLD_COMMIT) for downgrade verification..."
+git checkout --quiet "$OLD_COMMIT"
+git checkout --quiet "$ORIGINAL_REF" -- rust/ql/downgrade-tests codeql-workspace.yml
+
+echo "==> Running preservation test on downgraded dataset..."
+codeql test run \
+    --search-path . \
+    --dataset "${DATASET_DIR[0]}" \
+    --check-databases \
+    "$SCRIPT_DIR/downgraded.ql" "$@"
+
+restore_ref
+trap '' EXIT
+
+echo "==> All tests passed!"
diff --git a/rust/ql/downgrade-tests/66a489863649185f4a9770f894505803059a1312/upgrade_shapes.rs b/rust/ql/downgrade-tests/66a489863649185f4a9770f894505803059a1312/upgrade_shapes.rs
new file mode 100644
index 00000000000..e64d8f6582c
--- /dev/null
+++ b/rust/ql/downgrade-tests/66a489863649185f4a9770f894505803059a1312/upgrade_shapes.rs
@@ -0,0 +1,23 @@
+#![allow(dead_code)]
+#![feature(more_qualified_paths)]
+
+#[path_meta]
+#[key_value = 1]
+#[token_tree(list)]
+#[unsafe(path_meta)]
+struct S {
+    field: u8 = 1,
+}
+
+enum E {
+    V = 2,
+}
+
+trait Alias<T> = Clone
+where
+    T: Copy;
+
+fn f() {
+    let _ = try { 1 };
+    let _ = format_args!("{b} {a}", a = 1, b = 2);
+}
diff --git a/rust/ql/downgrade-tests/qlpack.yml b/rust/ql/downgrade-tests/qlpack.yml
new file mode 100644
index 00000000000..e2e42acf460
--- /dev/null
+++ b/rust/ql/downgrade-tests/qlpack.yml
@@ -0,0 +1,5 @@
+name: codeql/rust-downgrade-tests
+version: 0.0.0
+extractor: rust
+dependencies:
+  codeql/rust-all: ${workspace}
diff --git a/rust/ql/upgrade-tests/66a489863649185f4a9770f894505803059a1312/.gitignore b/rust/ql/upgrade-tests/66a489863649185f4a9770f894505803059a1312/.gitignore
index 3b4d77eb40d..1abb3d60e26 100644
--- a/rust/ql/upgrade-tests/66a489863649185f4a9770f894505803059a1312/.gitignore
+++ b/rust/ql/upgrade-tests/66a489863649185f4a9770f894505803059a1312/.gitignore
@@ -1,3 +1,5 @@
 *.testproj/
 *.actual
 *.log
+Cargo.toml
+lib.rs
diff --git a/rust/ql/upgrade-tests/66a489863649185f4a9770f894505803059a1312/README.md b/rust/ql/upgrade-tests/66a489863649185f4a9770f894505803059a1312/README.md
index a728458bef4..ecc94261ee5 100644
--- a/rust/ql/upgrade-tests/66a489863649185f4a9770f894505803059a1312/README.md
+++ b/rust/ql/upgrade-tests/66a489863649185f4a9770f894505803059a1312/README.md
@@ -1,6 +1,6 @@
 # Upgrade Regression Test for rust-analyzer 0.0.301 → 0.0.328
 
-This test verifies that the dbscheme upgrade and downgrade scripts correctly preserve data when migrating databases between the old and new schemas.
+This test verifies that the dbscheme upgrade script correctly preserves data when migrating databases from the old schema to the new schema.
 
 ## Running the test
 
@@ -16,13 +16,10 @@ This will:
 5. Restore your branch
 6. Upgrade the database to the new schema
 7. Verify that the old properties are still accessible via the new schema
-8. Downgrade the database back to the old schema
-9. Verify that the recovered old-schema properties still match
 
 ## Files
 
-- `old.ql` / `old.expected`: Query for the old schema (validates extraction and downgrade)
+- `old.ql` / `old.expected`: Query for the old schema (validates extraction)
 - `new.ql` / `new.expected`: Query for the new schema (validates upgrade preserved data)
-- `downgraded.ql` / `downgraded.expected`: Query for the downgraded old schema
 - `upgrade_shapes.rs`: Rust source containing test shapes for all affected schema elements
 - `run-test.sh`: Test runner script
diff --git a/rust/ql/upgrade-tests/66a489863649185f4a9770f894505803059a1312/run-test.sh b/rust/ql/upgrade-tests/66a489863649185f4a9770f894505803059a1312/run-test.sh
index 1dbbf2783b7..b5ae0d8a42f 100755
--- a/rust/ql/upgrade-tests/66a489863649185f4a9770f894505803059a1312/run-test.sh
+++ b/rust/ql/upgrade-tests/66a489863649185f4a9770f894505803059a1312/run-test.sh
@@ -7,7 +7,6 @@ set -euo pipefail
 SCRIPT_DIR="$(cd "$(dirname "${BASH_SOURCE[0]}")" && pwd)"
 REPO_ROOT="$(git rev-parse --show-toplevel)"
 OLD_COMMIT="${OLD_COMMIT:-491c373e076}"  # origin/main at time of this upgrade
-OLD_DBSCHEME="rust/downgrades/109496fd2f20f28a35e50b110859e74882ee80d6/rust.dbscheme"
 
 cd "$REPO_ROOT"
 
@@ -65,26 +64,4 @@ codeql test run \
     --check-databases \
     "$SCRIPT_DIR/new.ql" "$@"
 
-echo "==> Downgrading dataset back to old schema..."
-codeql dataset upgrade "${DATASET_DIR[0]}" \
-    --allow-downgrades \
-    --search-path rust \
-    --target-dbscheme "$OLD_DBSCHEME"
-
-trap 'restore_ref' EXIT
-
-echo "==> Checking out old commit ($OLD_COMMIT) for downgrade verification..."
-git checkout --quiet "$OLD_COMMIT"
-git checkout --quiet "$ORIGINAL_REF" -- rust/ql/upgrade-tests codeql-workspace.yml
-
-echo "==> Running preservation test on downgraded dataset..."
-codeql test run \
-    --search-path . \
-    --dataset "${DATASET_DIR[0]}" \
-    --check-databases \
-    "$SCRIPT_DIR/downgraded.ql" "$@"
-
-restore_ref
-trap '' EXIT
-
 echo "==> All tests passed!"