value lists in DDR pointing to layouts that no longer use them

[iMarcW]

I was going through the DDR to find unused value lists to remove and I found a couple that said they were used on a particular layout, when in fact they no longer were. If you look under the fields for that layout in the report, none of them shows the value list being used.

The value lists had been used on the designated layouts at some point in the past, but they were removed long enough ago (weeks, maybe months) that it couldn't be an issue with cached server data from the current session.

Could it be a situation like with global fields, where the information can't be permanently updated unless it's in single-user mode? Or is it a possible sign of file corruption?