Is there any public announcement on this? Since when is this option available? If this is a new thing the Mods can use, it should be widely known to scare signature spammers.
It was always possible. I remember months ago when theymos (or was it hilariousandco?) did the same thing with a group of users and banned them from showing their signature for 1 month.
But now they are banning for 1 year? Wow.