So 800k for the month?
at least... in aug ps4 was doing 130k minimum (really closer to 150k other than the last week). 130k * 5 weeks = 650k. (or 150k * 5 weeks = 750k)
so 650k + holiday boost + destiny boost.
if we assume a modest holiday boost of 10% then
130k*1.1 * 5 weeks = 715k (or 150k*1.1 * 5 weeks = 825k)
i think destiny alone adds a minimum 150k to those numbers.
so 850k is imo the absolute worst case scenario. 1M on the month is not unreachable.