Bethesda's "next gen" update for Fallout 4 continues to cause problems. Released in April, two years after it was announced, the 14GB patch was impressive due to how little it actually changed, aside from breaking everyone's precious mods. The timing couldn't have been worse, either, coinciding as it did with the planned arrival of the gargantuan Fallout: London mod. The team had to then delay the mod's launch while it figured out how to fix what the update broke.
The good news is that the end is in sight with the team and GOG, which is helping to distribute the mod, just double-checking that everything is working as it should. But there's a catch. See, the issues created by Bethesda's update proved to be insurmountable, and even after patches things like ultrawide support and VATS are still broken. So the team abandoned the current version of Fallout 4, and to play the mod when it launches you'll need to downgrade the post-apocalyptic RPG to an earlier version.
This shouldn't be a big problem for most players. GOG is offering a rollback feature for the version sold on its store, as well as working on downgrading options on Steam—either via a dedicated tool or manually. That covers most bases. But not the version sold on the Epic Games Store. Speaking to VG247, GOG confirmed that it would not be able to offer a downgrading option for this version of the game, at least not at launch, because EGS doesn't support update rollbacks.
While this issue really emphasises the need for players to have the ability to rollback their games, and how limited EGS is when it comes to handy features that we've become used to thanks to the like of Steam and GOG, all of this could have been avoided if Bethesda had worked with its community of diligent modders.
These fans are a major reason why Bethesda's games continue to thrive years after they're released, and Fallout: London in particular was hotly anticipated, as well as garnering a lot of coverage, so Bethesda must have known that it was launching imminently—and that the update would mess up those plans.
Hopefully GOG and the Fallout: London team will come up with a solution eventually, so Epic users won't be left out in the cold forever.