Unless you are travelling to the UK from another country.
This new Apple SIM seems a great idea for traveling.
I am not sure that there will be much benefit within your home country.
Even within the UK, this should allow you to choose between EE plans at will and natively on the ipad, and of course choose someone else should they get onboard. I think most carriers let you browse their website/app for free, which would probably allow you to renew a plan from the iPad but this should make it easier.
I wish this had rolled out last year though, I'm intrigued but there are no details and no support in Europe yet. Instant Hotspot looks like it'll cover my needs in the UK, but coverage in Europe (Netherlands particularly) might have me get the cellular.
Anyone who's got their cellular already care to post a screenshot of the options you get from EE?