FWIW, I've figured I can get to 81 by end of Nov by playing 2 ranked 18 hole rounds per day. My CDP is 105 days and I'll get 1195 XP next round. The 1st round usually nets me around 1800XP, and the 2nd around 500 -- using CC passes for both rounds too to get whatever extra XP that brings. I just turned over to lvl 76 last night and I should get there - assuming the clubs do stay available right to the end of Nov as WGT says.
So, considering you are 77 already, you should be able to do it, but you won't be able to skip many days.
As sad earlier there's always the 40% xp boosts you can buy in the pro shop.
Good luck!