Redirectors won't fix up / delete

Anyone might have any ideas why a redirector, which normally behaves as expected, might not be able to be fixed up / deleted?
This message is all i get in the log: LogUObjectGlobals: Warning: Could not delete

It seems to indicate its working normally at first. but then just won’t delete. eg:

Checked it wasn’t something wrong with perforce, and made a copy of the project and made everything writable with source control disabled, and still won’t work.

This was happening in 5.3, and still happening in 5.4.1