RLM - Standard Pack Rounding Issues

We have a special business process where we generate a special packing slip/delivery number used for direct supply payments.  We have many 1 or 2 piece returns the customer will process in their system, but before we get notified they send the release so we get many CUM exceptions.  They requested we move away from the customer receipt in transit calculation and move to the customer CUM in transit calculation.  Now the rounding to box qty is not happening so it seems the RLM processing rule standard pack rounding rules happen before the CUM in transit.  To me this seems