Sure someone's asked this before, I'm just a novice so don't know much - so I'll ask. I'm expecting to get 2 economy to premium economy upgrade vouchers in a couple of months time. I am looking to book LHR-DEL return sometime during Christmas/NY 2015. Buying upper class return would cost me 100,000 miles + £550 taxes. Is it possible that I book economy flights (42,500 miles + £280 taxes), use the voucher to upgrade to premium economy (I guess about £100 taxes), and then use miles to upgrade to first (25,000 miles + £170 taxes)? This way would cost me 67,500 miles + £550 taxes, in effect saving me 32,500 miles. What do you guys think?
(PS: This question is not about availability, so let's not even go there)
(PS: This question is not about availability, so let's not even go there)