found instore today at winton (bournemouth) coke had a sign saying 50% off marked price, so i grabbed the last couple and also tried the pepsi. also 99p.
went to another store (town centre) where there was only the pepsi varities marked up at £1.98, but they also went through with 50% discount.
2 stores so would hope its quite wide spread.
sorry folks, but only diet pepsi left in the above mentioned store.