Oracle Projects-Change Burden Schedule on Existing Transactions

We have a situation where we have a labor suspense project for each project unit for which we do not want burden costs to be created. We have accomplished that to this point by setting a fixed date against the one burden schedule we had set up. In a test environment, I set up a new suspense burden schedule and applied it to the suspense projects. I was able to import new transactions and show that they used the new burden schedule. However, I have nearly 50K existing transactions that are pointing to the original burden