The timeouts are a bit ridiculous, my session is always dead when the game finally does launch. Then a couple times a day the game can decide to freeze for ~15 seconds even in the main menu which causes the anti-cheat to trigger and close the game. Thanks. So I just don’t ever launch the game from UEFN.
My workaround is to launch the game from EGS first, wait for it to load, then start the UEFN exe file (as admin cause otherwise UEFN crashes with a login failure) from the game folder since EGS can’t handle starting two “games” at the same time. Note if the game crashes/closes for any reason, you can’t re-open it from EGS without closing down UEFN and VS Code first. Great stuff 
The UEFN executable is found in EpicGames\Fortnite\FortniteGame\Binaries\Win64UnrealEditorFortnite-Win64-Shipping.exe for those interested