I think Xbox beating PS4 this month is not a lock. Sony has the far superior bundles and those sell really well on bf. look at last year Xbox nearly took November even though pro launched. I believe it's because they had far better and more diverse bundles.
Even if Xbox x does 500k(double pro) I could still see them loosing by 100k. I could see
Xbox- 1.2-1.5 million(300-550k x's)
PS4 1.1-1.7 million
Switch- depending on stock 1-2 million.
Halo MCC will sell 5+ million copies(including digital)
halo 5 will sell 10 million copies(including digital)
x1 will pass ps4 in USA, and UK.