Can I do a REMVOL and an ADDVOL for the same range of volsers in one execution of TMSXTEND?
Yes, you can do this and TMSXTEND will complete with RC0, but you may not have the result that you wanted. The REMVOL range will be left in the TMC with all of the old data. If you are doing this to clear out all of the old data you will need to run this as 2 jobs. The first job to do the REMVOL, then the second to do the ADDVOL.