I had the same issue on my iPhone since the renaming.
I might have gone over board, but I logged off, closed all Safari windows connected to EDH forum. (Yes, I will keep calling it that.)
Then cleared all cookies, cache, and history that Safari held on the iPhone.
Finally, I logged back on and replaced the old bookmark with a new one for the logged on index URL.
All seems ok now.
Most irritating symptom I used to have was even with a logged on session already on Safari, opening a new pane to the forum prompted for a new login. Real pain when I could go back to the other pane and navigate the forum there without having to log on again. For 5 mins, at least.
Hope you are all able to sort this as easy as it turned out for me.
Let us know if it keeps working, because even though when you first visit a site and there's no cookies or history for it, I still tried doing this before I posted about it. And then again later, when I posted about it that it was fixed. Each time it works for like one relog, and then goes back to not working at all. It's like selecting the auto-log option turns on a flag, but that flag needs to be turned on each time you log in and auto-logging doesn't turn that flag on.