O2 simplicity - data charges?

[CryptKeeper]

I have a £15 per month contract (200 mins/ 200 txt). I got a N Series phone a few months ago and have started using it to check my email occasionally. Just wondering how much this will cost me in data charges? I can't find anything on google about their charges and their site is not specific.

 

[CryptKeeper]

On the sit it says up to £1 per day.

Therefore I take this to mean that if I use more than 333k (approx) data, then I get charged £1 and can use as much as I want for the rest of the day?