planned recovery from a certain transaction

I know questions like this have been asked before, but I hadn't seen one
quite from the same perspective (although I'm sure it's out there
somewhere).

We have a database which has one long involved procedure early in the
morning that updates all sorts of things, moves data around, deletes some
stuff, alters some DDL - you name it, it does it. The rest of the day, the
database is read only. Autovacuum is not on, it was killing performance for
it to kick on in the middle of the proc. Vacuum is run right before the
long procedure. We typically wait until the guy onsite verifies the
procedure went smoothly and then vacuum (Why? Because we've read enough of
"well, you would have been able to restore that if the autovacuum wasn't
running". We have a backup so this is just a checking before vacuuming is
technically unneeded.). Don't get me wrong, I'm a big autovacuum fan, just
not for this specific case.

The transaction itself works flawlessly, but every once and awhile the data
the it uploads from comes in flawed and we have to find a way to reset it.
This reset involves restoring a backup that was taken right before the proc
started. If we had the xid of the long running transaction, is there a
better way to reset it right before that transaction happened? Restoring
the backup is a lengthy process because several of the tables that are
affected are rather large.

Chris Spotts