You have multiple servers, so I would suggest running one virgin, with no addons see what that does.. then try just metamod and sourcemod with no additional plugins... slowly build it back up to where your at now..
The last update was the 9th besides that 'optional' one.. your only having problems since 'yesterday' seems strange. Are you on the server at the time, how do you know its crashing?
That warmup bug was a joke. I don't understand how that go threw, and more over I don't understand why the 'optional' update wasn't pushed. After the update Its slow to choose a team, and the warmup sticks on 0:01 untill someone dies.. mabey thats why.. sorry not ot just ranting..