ULA has one foot outside the launch business already. The BE-4 won't be ready for years. It's not inkkely ULA exits the launch business completely before it's ready, it's at a huge cost disadvantage even with the BE-4.

I doubt ULA will exit the launch business in the foreseeable future. Congress will not allow the US to be reliant on a single launcher, and they'll provide enough money to keep Atlas available.

ULA isn't out at least until BO has a few good launches under its belt, which means BE-4 or something similar is reliable.

The Vulcan might not fly in 2019 but it will fly by 2021. ULA still has money coming in and it will get more government contracts for quite a while, at least until Blue Origin New Glenn flies, so that will require BE-4 anyways.