I'm having this issue and was very glad to find this article. Disconnecting the LAN and opening via an nb file both work for me.
However, I did want to change the init.m file, but couldn't find the line "AllowDataUpdates->True,". Is there another way to know where to put the AutomaticWolframCloudLogin->False, line?
Finally, I wonder where this bug is logged? I couldn't find it under [bugs] in Mathematica support.