I got the stay 20, get 25,000 points, stay 25 get 40,000.

As far as I am aware, that is the maximum on the global promo.

There is a sticky at the top of this board with info for PLT's and PP's to optimise these bonuses, so you could have a quick look there, but I'm sure 40k over 25 nights is the max.

You can certainly switch from the Delta to the global promo, just change your earning preference back to MR points and register...