I know this must have been discussed endlessly, but I couldn't find a definitive answer.

I am in the Global 40k/25-nights promo, and I have a stay scheduled beginning on 8/31, the last day of the promo.

Does 8/31 count as a night in the promo? I will have 24 nights prior to the 8/31 stay, so it will make a 15k-point difference, since the promo also has a 25k/20-night level.