Not sure how long it will go on, but it's been going on since Dec 29th or so (may be off by a few days) while the website is being redesigned for Active Zone 3 and all.
Specifically, registers, EID recovery, file box and a few other features have been disabled since the Unlink and start of Active Zone 1, which was quite a while ago.
You can't even create a TSUKICHAT account right now even if you had an EIDv2, only people who joined before maint can.
Just be patient is my reccomendation. Feel free to post on thoe baords while you wait and all that. The wiki is also available at wiki.systemspace.link and you can read up on the project and all - some things are outdated but it's the best you've got for information outside of TSUKICHAT right now, though there will probably be a different format for Project information soon.