How do I get my iCloud account back?

[t12_incomplete]

I have a feeling that the iCloud accounts are stored in the phone memory and not on the sim card. So what you should have done is restore it to Factory settings and that may have deleted your account out of the 4s, and allowed you to install it into the 5s when you configured it? I am not the full bottle on apple products but I know iTunes only like to be synced to one source and so on. I suggest you contact Apple Care as your new 5s will be under them and let them talk you through the process, they have been very helpful when I rang them.