As a regular player on the other forum, after cutting my teeth on this one for a few years, it's ridiculous that folks have to guess what's going on behind the scenes, if anything. Maybe there's a fix, maybe not. It tried to identify me as human. But no explanation as to why? The apparent refusal by admin to communicate on this forum is annoying at the least.
In one of these threads I saw where this website was experiencing a DDOS, a Distributed Denial of Service attack. That's where a number of computers are used to access/pound a website so that no one else can access it. It can be done for a number of reasons (spite, prank, threat, etc.) but the result is what we have been experiencing. You can't get normal access to the server.
I have my own personal website hosted on a free site and it was allowed something like 10K user accesses a day. When I first moved it there it ran fine for over a year. I posted a thread in their forum, including some links to the site. That night my site was disabled because I exceeded the 10K limit that day. 24 hours later it was active again but within 3 minutes of becoming active it was shut down again because it reached the limit. I couldn't get those admins to understand what the problem was, so I gave up and moved to another site.
So the "I am not a robot" checkbox is there to stop this kind of attack. As a human you have to check the box each time you access the site. That's something that the DDOS software can't do. Bad guys do have ways of defeating that too. That's why at other sites you have to enter in a funny looking number into a box or check the boxes that have something, like bicycles or something.
I can't speak for the admins as to why they didn't post something, but with my personal website I couldn't even get to it because the host shut it down. There was no way for me to post anything for my users or do anything with it. I was completely shut down. I also know (previous life in IT) that sometimes problems are so bad that all your resources are directed at finding the problem, formulating and implementing a solution. Updates are provided verbally in meetings, which isn't possible here since our only access is via the website.
So they were probably very busy and didn't have the resource or means to notify everyone. Again, I'm just guessing. Maybe now that it's fixed they'll post something.