remote_dependencies_mode in pluggable database

Hello all,

We're experiencing ORA-04062: timestamp of package "object" has been changed

running Oracle 19.17 Pluggable database on linux RHEL 7

all the instances are set to signature, my question is does the Root container have to be signature as well?

This process is going from 1 pdb to another in separate containers. I have checked all PDB's and they are all signature. Root is set to timestamp

Would like to know if there is something else i need to check before going there. It doesnt make sense to me because if you can do an alter session then why would it be dependent on the root.