Client Certificate Change in SAP S/4HANA Cloud

My customer faces a severe issue with the annually Client-Certificate change in the SAP S/4HANA Public Cloud. Because of a small time frame, they are not able to change the certificate immediately at the renewal point in time. They need buffer time to do it.

The urgent request from customer: the previous now outdated certificate must be reinstalled again. It would be perfect if the old Certificate is also available in S4HC for another 4 weeks along with new one, so that Wilo can have some buffer time to make changes?

Is this possible