Is it possible to change the creation sign of a transaction type in set up after it has been used

 We have a number of transaction types for invoices created in AR from Projects Devolved billing where the creation sign was set up as Any Sign meaning we

have positive and negative value invoices instead of positive value invoices and negative value credit memos.

In order to match a -ve invoice to a a +ve one we have to create a nil value receipt, apply that to the -ve value and then to the +ve value

The transaction types have been used so an attempt to change this in setup results in an Error message APP-AR-96626: You cannot change a transaction type which has been used.