Recently joined the Android community with my first Android phone purchase. It's an unlocked Xperia LT28i with GB. I know ICS update will be available later on this year, however, not sure if I need to unlock again if it's updated? I used it with different carrier(s), as well as international travelling, and if updating OS will lock the phone, I probably will just stick with GB. Any input, guys? Thanks in advance!

-Alan