User38437727
There are no reports of US Mobile have any form of bootloader locking independent of carrier locking.
Some US Mobile contracts have carrier locking with different terms.
https://www.usmobile.com/unlock
Unlocking your phone
Why is my phone locked?
Some phones sold by US Mobile are temporarily locked from switching to other carriers. We do this to keep prices low and to ensure our best offers are going to our real customers. We will always specify if a particular phone is locked in the device sales' terms and conditions.
Compared to most carrier locks, ours is short — devices generally unlock after just 60 days of continuous usage on a US Mobile line, unless a longer period is specified in the offer terms.
How do I unlock my phone?
After the required period of continuous usage on a US Mobile line, if your account is in good standing, the phone will unlock automatically. We’ll take care of it — no action needed from you.
If the locked device is not activated on a US Mobile line, it will still unlock automatically 12 months after its first connected to the internet
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