You can do toolchanges at G30 reference points as well.

I do tool changes at G30 W0 U0 while the B axis is usually just left at G28 B0. On our 21LMS the G30 locations puts the tool changer around x0 z8 off the chuck, works great for just about any program.

You can change the G30 locations by enabling PWE and the locations are around parameter 1500 iirc (no book in fornt of me)

No ladder rewrite, service tech needed, you can edit this in 30sec standing at the machine.

Be forwarned however, from my experence, you can set the G30's to locations that will cause interference, IE with the turret burried in the chuck and the sub plowing in behind them, i dont belive there are any safeties beyond the g28/30. So be librial with that 1% rapid override the first time.

EDIT:

A quick Google shows that g30's parameters are around param 1200, which i believe is correct. I found them originaly by just paging down

-Jacob