I'm not too worried about this. For an MVP, they're allowing up to 25% to be bought, but for a gold only 12.5% and just 6% on a 75k.

Since I have some partner miles this year, I'm looking at ending up about 4k short of 75k (90k, really). With over 80k BIS on AS and DL this year, I'm totally fine with buying up the last few miles instead of sitting them out.