If you sell the car half way through a month. by surrendering the tax. you'll only get full months refunded. so instead 0f 3.5 that it is you'll only get 3.
the catch is that the person who bought that car half way through a month will have to pay a full 6 or 12 months.
so there's a 1/2 month lost. but a 1/2 month gained.
multiply that by a few million of the cars being sold and bought everyday. and you have about 50 million pound a year scammed.
when they do it. it's legal
when you do it. it's fraud.
stuff them. it's everyman for themselves. scam away