Restore Storage question

Perhaps someone can shed some light on a little problem we encountered.

Over Memorial Day weekend, we did a whole battery of backups.  SAVSTG,
SAVCFG, SAVSECDTA, plus we did the whole SAVSYS and SAVLIB *NONSYS route too.

We were doing a software upgrade, but due to complications, ran out of time
so we went ahead and did a RSTSTG to bring the system back to the
pre-upgrade state.  We've done this before, everything went normally, but...

None of our SQL collections worked properly.  Any program that attempted to
open a table in a collection terminated with a MCH5601 error and a message
concerning "invalid template"  Oddly enough, we got the exact same thing
with the WRKPRB command.

It seemed like it might have something to do with the commitment control,
and the only programs that blew up were those that opened the tables in
Update or Output mode.  Read only programs worked fine.  These same
programs were working just fine at the close of business Friday, a few
hours before we did the SAVSTG.

We tried the RSTSTG twice with identical results and finally fell back to
reloading the OS and applying the other saves.  That got us
working.  (Although we still have some issues with the SQL collections)

I always thought a save storage was a complete system image, so I'm
confused at how this could happen.  I've never encountered this before on a
restore storage.