pre-order ?

[MrSteve]

I'm guessing it will be either this friday (one calendar month before release) or next Tuesday (4 weeks until release)

Remember, although no longer a small indie developer, they're still small compared to a lot of other developers. All their resources are probably tied up in making sure the game is a good as it gets, for release. Also, larger games have earlier pre-orders, because they can afford to put it out earlier for pre-orders.

AAA title like Fallout 4 Pre-order six months plus in advance
Title like SOMA which is still kind of Indie, much less.