hi guys, i have updated(7.0.6)my i phone 5, active with R sim 9 pro. is it safe to go for "Carrier Update" . i fear it may lock to original carrier o2 uk. moreover i cant dial USSD code and 3 G switch is also missing. 1. carrier update will not lock my iphone 2. ussd code and 3 g switch will come back if i update the carrier settings update?