Our accounts' CoA was in a mess (with lots of split ranges) after years of ad hoc additions and changing reporting needs. As a result we relaid our accounts moving the nominal codes around and the current invoices were transferred across (the posted entries having their nominal codes changed but not the invoices themselves).
We have recently had to credit a transferred invoice and the nominal code on the invoice is now non-existant (having been moved) and is on the credit note as non-existant. It would have been nice if the nominals on the transferred invoices had been corrected but it was missed as the Invoices are not part of the accounts - only the updated ledgers which use them as source information to post the transactions.
Due to a recent reporting needs change we have also had to shuffle some data since the relaying. This means that should any of the invoices with shifted nominals need crediting the nominal credited will be the incorrect (original) nominal and not the correct (moved to) nominal.
When editing posted invoices and credits there is a warning that the posted data will not be updated, so why not allow all fields to be changed?