I think between a possible host migration and possible software updates and feature testing, there are going to be possible down-times and small to medium glitches.
I think the staff is trying to do their work in the background while trying to keep the forum active vs. taking it completely offline for maintenance.
Now, this is just a guess, and I have no direct knowledge of the back-office work.
Just be patient if you are having trouble logging in or getting some kind of error when refreshing the page.
Try not to keep refreshing the page, as that might be seen as sending too many requests at once, and some servers have issues with that.
Just wait a while—say, 60 minutes—then try again.
Anyway, if this is wrong or not good information, a moderator is free to delete this post.