The forum and wiki will be going offline for about five minutes on 2014-04-12, between 07:00 and 07:15 UTC.
For convenience, this means:
EDT (USA east coast):
2014-04-12, 03:00-03:15
BST (UK):
2014-04-12, 08:00-08:15
AEST (Australia east coast):
2014-04-12, 17:00-17:15
The intent is to install security updates on the server which hosts the forum and wiki. A particularly critical security fix has just been released for the OpenSSL package, which is not used for the forum or wiki, but may impact other services on the server. These will be non-disruptive to functionality, as the server is running a stable OS release that gets critical fixes only.