Interestingly I have noticed this same behaviour sometimes too. Weird thing is though that it usually shows me the correct rename string, but every now and then an “old” one crops up.
I noticed old values in e.g., the save-as too sometimes, but those I can sort of explain by the use of snapshots; I guess when you save a snapshot, all fields are saved, even the invisible ones (e.g., rename string when renaming is deselected). When later you reselect "rename", the “old” string is shown again.
Perhaps this has something to do with the issue as described here too?
