Well...this is pretty darn simple and I found this out by mistake. I lvld a druid from 1-85 but when I hit 70 me and my friend had enough honor to get full brutal set so we bought it and did some games to break from leveling and we got 1.7k rated..We got achievements and everything. then we moved on and lvl'd when we was lvl 75 we noticed we still had the arena team and it was still 1.7k rated so we thought maybe it would go away when we hit lvl 80 but it did not...then we reached 85 and we was still on the arena team and it was 1.7k rated and we were lvl 70 when we made the team and did arena on it. but now we are both lvl 85 in greens and 1.7k rated and a higher conquest cap to gear faster.
So you can level a toon if you really wanted to lvl 70 hit 2k rating or w/e and move on to lvl 85 so you would have a higher conquest cap soon as you hit lvl 85