Cost distributions in PA module in R12 during GL close

In our system, we create customer invoices only from PA expenditure items or events.  Because of our flow, our PA module is the first to close at month-end.  Since labor distributions are the trigger for creating ICO transactions and cross charge accounting events, what, if any, are the ramifications of running labor distributions when PA is open for the new month, but GL is still open for the current month in R12?

In 11i we were able to run PRC: Distribute Labor and it wouldn't affect the GL balances; however, since upgrading to R12 we are finding when labor distributions happen is key to how all other transactions get processed.  We are afraid if we run this process it will cause issues with the GL close.