Two questions:

1) I just bought aa S500i and I believe it's CID52 still (haven't checked it yet). Let's say I unbrand it and unlock it. After that, I update the phone using SEUS. Will my phone stay unbranded and unlocked forever? If I'm upgraded to CID53, what won't I be able to do?

2) Is there any other way, a simpler way, to check what CID my phone has without using XS++?