Upgrade coupon question.

Looking for peace of mind. I booked a trip, on Acela, in about 2 weeks. I booked business, using my CC points and then I planned to use an upgrade coupon to move to first.

Two questions: There's no option to upgrade. A call to customer service (very nice person) told me that I will be able to use the upgrade coupon 12 hours before departure? Is that right? Also, will there be any issue using the upgrade coupon since I booked with points?

Edit: thanks for clearing this up for me. I've canceled and rebooked, using my CC, instead of points. I'll be setting a reminder to try my coupon at the 12 hour mark. Hopefully, I'll be sipping a Bloody Mary in first as the sun rises.