Custom Fields with value must be unique across all assets

[AspireJason]

When the "Value must be unique across all assets" box is checked for a custom field, does that include an Assets History?

I recently had an asset (Cabinet) with a custom field value of "T03". We then had a need to create another set of separate assets with a custom field that also have a value of "T03". So the previous asset (Cabinet) value was changed to ecabT03 so it would not conflict with the unique requirement of the new asset T03. But I still get error and I think it is because the original asset has in its history a value of T03 now causing the conflict.

Practicality - Assets custom field values may change as interior components may change. For example, A Cabinet is identified by its Proprietary Software on a micro SD card. That SD card can be removed and placed in a different cabinet now changing that cabinet identifier to whatever the micro SD card designation is. Thus requiring a change in that cabinets custom field value but if the history blocks it because it is not unique how do you resolve without deleting an asset and recreating it each time a change is made? I need to keep the unique values to prevent errors of duplicity or mismatching.

Example:
Cabinet (A) is designated as ecabT03. SD card in cabinet is designated T03
Cabinet (B) is designated as ecabA99. SD card in cabinet is designated A99.
Cabinet A is reconfigured and SD card A99 is installed in it now changing that cabinet designation to ecabA99.
Cabinet B is reconfigured and SD card T03 is installed in it now changing the cabinet designation to ecabT03.
But since the history of each cabinet shows the custom value previously used, even though not currently used and changed, it gives the error "The snipeit ecab designation 10 must be unique"
It looks like once an asset is deleted the issue resolves because the unique value requirement doesn't look at deleted assets.
Or am I wrong and this has nothing to do with the asset history?

[AspireJason]

Issue resolved. I think something was corrupt with the original asset I was changing. Not sure of the issue but by creating new assets and testing it seems to work fine not like I described above.