On Thursday afternoon I initiated an upgrade of Discourse (the software that runs TiltForums) which failed. In the past when this has happened, everything has been rolled back and the original state was restored, but in this case that did not happen and the software would no longer boot up. After a couple days working through the problem I decided the best course was to restore from a backup taken Thursday morning. There is probably around a 12 hour gap between the time of the backup and the time of the outage, during which time any new posts have been lost. My fault, I would normally take a backup before performing an upgrade but the past ones have all been very smooth and I got lulled into a false sense of security.
Thanks all for your support of, and participation in, TiltForums. Sorry for the issues!