When a z/os dynamic I/O change is in progress, and CA Allocate is in its volume selection function for an allocation, there is a rare chance of an
IEA995I SYMPTOM DUMP OUTPUT
SYSTEM COMPLETION CODE=0C4 REASON CODE=00000004
DATA AT PSW xxxxxxxx - D2037000 40004177 00044144
ST03707 test apar has been written for this new defect.
Quiesce the z/os system before implementing the dynamic I/O change.