if one purchases the game now do they get the coming updates as well
yes.
there will be a panel at the top of the screen saying "You own this adult game" with the price you paid and how long ago. with a download button. click that and you will have the current download options available.
i purchased it nov 2021 when only episode 4 or 5 was out but can download ep 7 without issue. so dont worry about it.
it also says the game is currently on sale.