As far as I know all CT stations do is test cars. They have nothing to do with removing them from the road (except if they fail so badly the owner os only allowed to drive home or to a garage) and they wouldn't necessarily know the procedure to 'SORN' them.
I've now declared the car as 'hors de circulation', got the acknowledgement from ANTS and sent it off to the insurance company. I'll post with the result.......comme d'habitude it'll take them a week to reply.
Remember it's better to have a gun and not need it than to need a gun and not have it.
You don't stop playing because you grow old, you grow old because you stop playing.