There is usually a pretty simple solution to the OP's concern, which is a status challenge/match. It is perhaps a bit late now, but if put in that situation, I imagine United could have been persuaded late last year to allow a "challenge" to Gold or Platinum over a 3 month period. The argument is easy "I flew nearly 50K in 6 months - I'd like a challenge that would reward me if I keep up that pace".

Then, after flying 22K in the first quarter of 2015, OP would be platinum, with a likelihood of retaining it through 2017.