Dreamland Tokens Question

Bit niche, but hopefully someone will know.

Taking the kid to Dreamland tomorrow, obviously getting them a wristband so they can ride all day - but wondering about the best way of paying for rides when she wants a grown up to go on with her.

Won’t need more than 10 tokens split between Dad/Mum/Gran - wondering if Dreamland really do change their tokens each year, or can I get away with buying 20 tokens (cut price deal), use 10 and keep the other 10 for next summer?

The website does say you can’t do that - but just wondering if you can get away with it? Has anyone done it? Or do they change the token design each year to stop you?

Thanks