I have a W fare for NRT - SFO. PZ = 0, I can get confirmed upgrade to PP immediately if I use GPU and get waitlisted for Polaris.
My preference based on scenarios:
1. PZ>0 -> Use GPU to upgrade to Polaris
2. PZ=0 -> Use MUA to upgrade to PP
I don't want to end up using GPU to upgrade to PP.
If I use miles today to upgrade to PP, and keep monitoring PZ space, can I later on cancel/refund my miles back to W fare if I see PZ>0, and apply GPU to get to Polaris?