In the England forum, Marco has posted to advise that the £5 is changing, followed over the next few years by the rest of them. The Scottish banks are also changing their notes on a similar timescale, and to the same sizes as the English ones.
These are the new Scottish fivers. The RBS is much improved, going in my opinion from the worst to the best. There will be a short handover between designs but any hoarded notes will lose tender status at the end. Like the English ones they will still be exchangable at the issuing bank.