We had a report of ODSZUPDZ recompiled with COBOL V5 and S0C4's were being received.
(Thanks go to COBOL support for the following explanation.)
It turns out that when module ODSZUPDZ is built with the COBOL 5.1 compiler, it has a deferred segment.
The module ODSXUPDZ is loaded (via a directed load) in ASID x and the LFMD for it is built in this ASID with a valid loader token.
Later CEEPPOS tries to load the deferred segment of the module for which LE does not have addressability to the LFMD, because the LFMD resides in ASID x, but the deferred segment is being attempted to be loaded in ASID y.
The only solution thus far is to add the module into LPA.
When the module is loaded from LPA, the LFMD is built in common storage that can be accessed from any ASID and allows it to work.
Ed