I found the bug which led to this new enhancement. Here is a summary of the issue prior to the latest release:
"In the current model, UBR/UER calculations are done when revenue or invoice is interfaced. There is a known issue with this model when a interfaced revenue get rejected by GL or a interfaced invoice gets rejected by AR. Tieback
process will clear off the ubr/uer on the rejected documents as the UBR/UER will be rederived when they get reinterfaced. This is a technical limitation of the current architecture. We are looking at a solution which will not clear off the UBR/UER at document level during tieback process and will reinterface the documents with the same UBR/UER."
Due to this limitation customers were having to do manual GL journals. When they wanted to start using Third party global control accounts it was restricting them from being able to do manual journals, hence we had to fix the root issues before they could continue using control accounts.