This can't be stressed enough. If you suddenly can't access the forums or the wiki, then send an e-mail to admin [at] jpmetal [dot] org or find some other way to get my attention. I don't use most forums these days, so e-mailing me is the quickest way to get my attention. Make sure to include all known IP addresses that couldn't connect. It is imperative that I let the host know that you were blocked by mistake. I don't recommend the use of proxies at all.
I think it would probably be useful to have the page redirect to the admin email or something if it fails to load.
Sadly, there's no way to do that. If you get blocked by the server, then you get blocked. It's probably for the best, though, as cyber attacks have become more rampant in recent years.
With that said, I do feel for some of our visitors who've had problems accessing. E-mailing me is the quickest way to get my attention. You could also try contacting another member by means of proxy to get your issue resolved.
If you use Opera, you can try turning on the browser's own VPN function. Chances are that it should work. That's one other way to bypass these blocks.