For the past few days every time I tried to log into the site I'd end up at some motor blah blah site. I finally got in tonight.
I've logged in at least 20 times in the past few days. No problems for me. If you check out the various forums, you'll see many posts made during the days you were somehow being blocked.
Thanks. I thought I had a local PC problem, but then I realized this was the only site doing it. Very strange.
Looking deeper, I see that my usually long list of alerts went away. Also @Rexsio in the MINI Cooper SE forum says he's been having problems reading threads. I can see posts from Tuesday, but I don't see any that were posted on Wednesday. I didn't try to post anything on Wednesday, but the site felt the same to me.