I wasted an hour on that last night, trying to prove to someone it was fake.
Like they said it was from @YouGov but nothing on their twitter feed or website.
So I pulled up the poll the +/- figures were based on (Dec 6) and they'd got 4 of them wrong, i.e LDs 12 (+1) when it would have been -1. BP and Gr saying -1 when the number quoted was unchanged.
They couldn't even be bothered to fake it properly.