This is specific to the the V12 function/catalog level.
Execution of a Merger Copy Strategy is from a Source (V11 NFM) to a Target running V12 Function Level..> V12R1M100 Catalog Level...> V12R1M500
The execution receives this error:
RCM0310E - SOURCE TABLESPACE DBADMDB.PRVABCD IS IN EXTENDED RBA FORMAT
AND TARGET IS NOT A V11 NFM SYSTEM.
RCM0102I - RC/MERGER COMPLETED WITH ERRORS.
RETCODE = 16
The new V12 catalog/function level was not being evaluated correctly.
DB2 Tools: R20
Source : DB2 V11 NFM
Target: Function Level..> V12R1M100 Catalog Level...> V12R1M500
PTF SO08330 will resolve this issue.