Unfortunately they have stopped the "return any day ticket" they used to do for £15. I was there last weekend and intended to get one for my boyfriend as he was using one of my annual pass vouchers but they told us that they no longer do them due to the new season pass. They still do the return next day ticket for £10 but that was no good for us.
Also on the latest production run of Kelloggs Variety.
Ok I stand corrected! In that case it's definitely worth doing. When I tried it displayed as £55, although I couldn't get passed the 'enter your voucher code' part.
(lol) I meant £1 not £50 for a multipacks of crisps (lol)
Not sure about stacking but end date is 31st may