The gamertag is "AJ"
AJ is the original tag
A J is a spaced tag
Custom is original
C ustom is spaced.
Back then, microsoft made it to where if the original tag was taken, you could space it and it would say its available,
Since microsoft patched this you cant do it anymore but gamertags that were spaced still roam.
Be warned that if you have a gamertag that is or has been spaced, if you try to change it and put it on another account, it will still say its taken and you cant take it back.
Thats why most people account swap rather than gamertag swap.