There are probably meaning layers to this move by the Government.
The first being that this is a psychological warfare tactic on the people of Gibraltar in retaliation for their recent protests on Nov 1, Nov 5 and Nov 15.
The Government probably thought it had things well under control, until people started rising up. It's time to knock Gibraltarians down and show The Rock who really rules. Oppression works to take away hope. How's that for believing in the false hope of the vaccines and their kind of "papers-please" freedom of Gibraltar's new normal.
The second being that a winter lockdown has been planned for quite some time. They've been warning everyone – have you listened to the talking heads the last few months. All these news releases about the surges and possible lockdown was to programme this into your psyche.
The third being that Gibraltar is once again a test bed to see how this kind of totalitarism works right before the holidays. Other world leaders in bed with this plan are watching.
Of course, Gibraltar could decide to flourinate the water to keep everyone docil like the UK did recently, and like they did in the Nazi concentration camps.