If I unlock your account, you understand that this is the only chance you get right? If you get another UID mismatch strike, your account will remain banned.
So decide if you want to use your brother's laptop to play Vice War or if you will be ok with your computer to do so. Also, whether you reinstall Windows later in the future (which changes UID), it matters not, no exceptions to the rule. Are you sure you want to be unbanned right now? Cuz I would advise you miss the beta in favour of the main event.
