Any z/OS V2R2 JES2 member in the multi-access spool (MAS) will not be able to read the checkpoint containing a large valid change log without encountering abends. z/OS V2R1 JES2 members in the MAS will be able to read the checkpoint appropriately, but the z/OS V2R2 members will not be able to WARM start. If the entire MAS is comprised of z/OS V2R2 members, then no member will be able to process the checkpoint and this may result in a required COLD start.
Please see APAR OA51558 for additional details.
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