This is advanced warning that we will close for an important upgrade to a newer version of vBulletin on Saturday 26 April. The work will begin at approximately 11am GMT (12pm BST, 7am EST, 4am PST), and it should be a quick update with minimal downtime (approximately 10 minutes). This is a bug and security fix release to the system, so will not mean any new features. [This is now complete]