When you refund your legion preorder from blizzard do they take away your level 100 boosted character? If they don't you can pretty much get unlimited boosts as they are legally obligated to refund you even if you do it 9000 times. Also, you get about 500g for each 100 boost if I remember correctly. Even if they do remove your character you could have sent the gold to another character and exploit this and get a lot of gold.
The toon is not removed but is locked and you can not login to the world with that toon until u will buy Legion again and you won't have additional boost as that is used to unlock previously boosted toon.
