Quick answer: Unreal Fix Up Redirectors action losing references on dependent blueprints? Fixup deletes the redirector; references that weren't migrated point to nothing - run Fix Up after every move, not in bulk.

Bulk-moved 50 assets. Ran Fix Up Redirectors. 12 blueprints now have missing parent class references.

Fix Up immediately after move

Right-click moved asset > Fix Up Redirectors. The dependency walker catches references while the redirector still exists.

Or use ResavePackages

UE4Editor.exe -run=ResavePackages -fixupredirects

CLI tool ensures every reference is migrated. Use for bulk operations.

Audit before Fix Up

Reference Viewer on each redirector. Confirms which references will be updated; deleted refs without warning is the bug.

“Redirectors are bookkeeping. Bulk delete bypasses the bookkeeping.”

Discipline: never bulk-delete redirectors. Either Fix Up Redirectors per file or ResavePackages on the project.

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