Valve releases the updates without notifying anyone beforehand about the updates. When Valve releases an update it takes some time for plugin authors (Sourcemod, Metamod, Mani Admin Plugin, Mattie EventScripts, ...) to update their releases. Valve has been co-operating before with server plugin creators with this kind of stuff by informing about the upcoming updates. Nowadays they don't do that and every time there is even slightest update it's a random chance whether the plugins work or not. If they don't work then we wait... so now we wait.