Interesting impact of two policies
Recently checked on the cost of up-fare a 2,100 mile 2-segement route, mainline+UX, K fare; change flights offered a sightly longer 2,500 mile routing (1hour extra, all mainline), A UPDI fare for $160-ish -- normally I have not been a taker in the past.
But with 200% A fare PQMs, it was 2,900 PQMs extra -- or less than 6 cpPQMs (semi-MR territory) -- and likely to being PQM challenged in the next year could avoid a future MR;
and a guaranteed F seat on mainline
I will admit to my first buy-up -- I have moved to the dark side.