SQL Server Assembly on Failover cluster after Framework update

We have database that relies on a CLR assembly. The assembly references other assemblies. After a Windows Framework update we need to drop and reinstall the assembly to have it work.

Now the issue is that the database is part of a failover cluster. Yesterday the secondary server was updated and with it came a framework update. The assembly no longer works on the secondary, but we cannot reinstall it because it is a read only.

The primary server hasn’t been updated, so no point in reinstalling the assembly.

Does anybody has experience in dealing with these sort of issues? If so is there a recommended way of updating assemblies?

We could do a failover and update the assembly. However is this case the assembly doesn’t match the Framework on the other server. I guess we need to do a failover, reinstall the assembly and update the other server to the same Framework?