Be aware that a 7 month walk is less likely to be successful because anyone w/ home resort booking where you’re walking may have already blocked you or can block you at any point as you walk towards your preferred dates.
There will likely be movement as the 7 month window opens up for early Dec. and folks modify their existing reservations to move elsewhere - if you look at the availability charts linked above by
@bluecruiser you’ll notice that the two biggest resorts - SSR & OKV - have very little availability at 11, 10, & 9 months for 2 br.s in early Dec., then things open up at 8, 7 & even 6 months before availability starts to disappear again.