How does an NCP season ticket work?

Does anyone know how season tickets work on an NCP car park where standard paying customers would normally take a ticket out of the machine on entrance and then submit it to validate when leaving the car park? I realise that it would probably be displayed on the dashboard if it were an open air car park, but this specific car park is a multi storey where you have to get a ticket up front before the barrier will open to let you in. Thanks in advance.