Two relevant things can be worth mentioning related to SCHC:
When the Partial IV value is compressed, a device will have to rekey more frequently. For instance if only 3 bits of the Partial IV is sent then the maximum PIV before needing to rekey is only 7. (So in essence usage of SCHC can lower the maximum Sender Sequence Number).
Any time the SCHC context Rules are updated on an OSCORE endpoint, that endpoint must perform rekeying.
Two relevant things can be worth mentioning related to SCHC:
Reference: https://datatracker.ietf.org/doc/html/rfc8824#section-9