I understand that when you use the patch unlock method, the phone will remain unlocked unless you flash with new firmware. If the firmware needs to be updated, the phone can be re-unlocked a second time using the same method (generating new patch file), correct?

Does patch unlocking affect the ability to subsidy unlock?

I'm trying to unlock an AT&T branded w580i. I would prefer to use subsidy unlock method, so I'm having a friend who is a AT&T customer try to get me the code. However, if there is a delay, I might use the patch method so I can start using the phone right away. I just want to make sure that these two methods of unlocking will not have compatibility issues.

Would I need to reflashed the unlocked phone to lock it again before I enter the subsidy code?

Once a phone is unlocked by subsidy code, is there any way it would get locked again? I know with Moto's, that is possible if you flash with a locked monsterpack. If it's possible to be locked again, would the same subsidy code work again?