I'm having the exact same problem but mine doesn't seem to be intermittent. Over half of the servers I try to connect to, the screen will flicker and not do anything. After I click connect a second time to the same server, I get "Connection Failed" (I assume the server is full? Was previous issue in earlier experimental builds)
However, on some servers that I click connect the game will just instantly freeze as described here. I have made sure my BEService is running, rebooted my computer multiple times, reinstalled experimental, checked file integrity, and disabled all overlays. I haven't been able to connect to a server once.