I use HP-UX & need help with time.
I use a script to create a date stamp: /bin/date "+%m%d%H%M" to get: 12080826.
I need a way to use the "touch -t" command to create a
file with a timstamp 30 minutes prior to that stamp. (12080756)
Can anyone help?

The timestamp is in seconds, so to get 30 minutes prior, subtract 1800 from it.

You need to have your date in epoch seconds, subtract 1800, then format it back so touch -t can use it.

Perderabo's datecalc script in the forum FAQ does this kind of thing for you - look at the date arithmetic thread.
Yesterdays Date/Date Arithmetic

datecalc does not handle time, just the date.

This question involves a timestamp in minutes, not seconds. Simply subtracting 30 (rather than 1800) from it would not work shortly after midnight.

Try this:
perl -e '@d=localtime time()-1800; printf "%02d%02d%02d%02d\n", $d[4]+1,$d[3],$d[2],$d[1]'

If you have not installed a recent version of perl, the HP supplied /usr/contrib/bin/perl, which is very old, should work.

Excellent. I will give these options a try. I appreciate the help!!

Anybody know how to transfer the date into "epoch seconds" ??

Try:
perl -e 'print time(), "\n" '