And normally that's what you'd want: If they take a few days to re-issue your ticket you would not be happy if somebody else then grabs the seat that you (though to be) upgraded into!
Unfortunately I don't think there's a way to trick the system and have both an Award and Coupon upgrade if the availability is only I1. You could consider booking one in class A (if available) since that will also get you a lot extra miles. Or buy the award and one Economy ticket now, and hope that close to departure the upgrade will clear.