[any way to exit pit to get to white march exp?]

You can't exit it once you enter. There should've been a lore friendly warning (as opposed to a massive pop up box) however the game does create a 'PRE-END GAME' save just before the jump so you should have that which would save a lot of re-doing everything.

 

EDIT: can't

I did see the warning, but that was before the expansion.  I was hoping they'd implement some sort of teleporter, ladder, hole, something  

[any way to exit pit to get to white march exp?]

I'm all the way at the end of the game, entered the pit, killed everything, etc, and one thing left to do is the final click to release the spoilers.

Is there any way to get out of here to attempt the white march expansion?  or just keep reloading old saved games until I find one close enough?  (which I always hate doing in games like this :/)