i am babysitting a reservation where as of now i expect a good chance of clearing CPU, but don't want to be in coach. if i read the rules correctly, an RPU or miles upgrade cannot be applied online inside T-24. is this true if R>0? if so, what is the best strategy:
1. apply RPU/miles now, and pull it back later if CPU continues to look good?
2. wait until just before T-24 and if no CPU, apply miles/RPU?
3. something else?