If it was me ... I'd buy the ticket and squeeze the budget. If you gamble on the points and are wrong, you'll have to squeeze the budget even more. Or you might make the 2750 but be buying more of things you don't REALLY need which will cost more in the long run. Also, if you go twice a year, I doubt our dollar is going to improve for awhile so the discounted ticket will still be a good buy regardless.
FWIW, we are going April and September and I have enough tickets/points now for both trips. But the April trip is just a 4 day quick trip so we are buying discounted tickets and saving our nonexpire tickets.