I had the same problem, and solved it the same way. However, I noticed My Home Assistant VM and one of my docker containers were no longer available from WebUI after making the change. I figured the update must have caused a port conflict somewhere, but haven't been able to figure it out. Possibly Healthcheck?
Rolled back to my previous version of Gluetun, and logs show that it is healthy now, but I still can't access the docker containers I had routed through...