I think anyone who is currently on Textanytime or talkalot might aswell use this.
£10 unlimited text to any network in the UK
£15 unlimited text and web
It ends on the 31st october but you'll stay on that tariff unless you change it, after that you will never be able to get text and web again unless they bring up another promotion like this.
Just ring up customer service and ask to have it changed manually so much easier and less glitchy then doing it on your phone.