[MiRai]

Originally Posted by Miiru and in many cases leveling a toon (if there's no premade 110's) to test stuff which is only possible at maxlevel

Blizzard created a level 110 premade PvP server for alpha two months ago, but it's partially restricted.

http://us.battle.net/wow/en/forum/topic/20742614769

However, I'm pretty sure we've had max-level premades available for PvE realms at some point in the past several betas so that more content, outside of leveling, could be more thoroughly tested.