I found the following reference to PETAPE's challenges due to IBM changes to CMS TAPE command.
Append on 06/27/90 at 09:49 by Stuart McRae of Systems and Telecoms:
...
And as for 'shareware', I recently got several disks in an attempt to find a
couple of utilities for specific tasks. First, nothing I've found did what I
wanted, but more importantly here, several of the things I found on the disks
which looked useful either did not work or hung the PC. In all my years of
using code from VMSHARE or the Waterloo tape (since early VM/370 days),
I can remember few problems with free VM software (except when PETAPE was
caught out by an unfortunate change in CMS).
...
Mark A. Stevens