They don't really change all that much.
The movies will change, if you're in a resort that shows movies (like POR does) then the movies showing will change even if the times/locations don't... but nobody really knows the movie rotation until the first of each month when the resort puts out the new list.
If you found one from this month or last month online someplace, you could expect more of the same for next month with the exception of holidays (but you don't seem to be going during a holiday anyhow).