Epic Games have now stepped in to help.
Epic Games statement:
"To assist developers who are left in limbo by the new engine and service incompatibilities that were introduced today, Epic Games and Improbable are together establishing a US $25,000,000 combined fund to help developers transition to more open engines, services, and ecosystems. This funding will come from a variety of sources including Unreal Dev Grants, Improbable developer assistance funds, and Epic Games store funding."
Epic Games CEO also tweeted his personal views on this: https://twitter.com/TimSweeneyEpic/status/1083475839721897984