@Brad ******
if you're on a 30 day extension now, you can't have your current stamp cancel,
You aren't on ANYTHING to do with the 90 day Non-O visa until they ink it into your passport :) (even though they're gonna back date it from the date you applied ;) for it) .
So that means when you leave you'd need to get a re-entry permit to get stamped back in for the same expiration date you have now.