Hi Nikhil,
As per my understanding please ensure the following once the upgrade is done -
1. Check the relevant RFC's in SM59 between CRM and ECC systems.
2. Check the adapter object relevant to applicable condition records.
3. In any new upgraded system, as IPC is a part of VMC, you need to activate the VMC in the upgraded system. (Your Basis team should be able to do it)
Hope this will help
Regards
DJ