I think I have the same problem as you - I like to plan for next year and buy tickets for my trips next year while cheap but at the moment, I have enough to get the status that I am aiming for. I have another CC: a non-airline travel credit card with cash back. So my current plan, if push comes to shove is just swap charges between these two credit cards in order to maximize rewards, but sadly not quite PQPs. I will charge any purchases for this year on my other CC, and what I would have charged to it next year, I will instead charge to my UA CC to get PQPs.

TBH, I really dislike giving any airline CC company any more business than what I need to meet my status for the year.