Ok, so I was playing a few games of lockdown last night. Everything was working fine, I had my T1 gear on, and just having a good time playing some T1 games.
However, in my next game, my costume appeared to be turn on(and several others too.) in a game of Lockdown. I was still in a T1 game, so I kinda shrugged it off, and continued playing the game.
The next game after though...me and several of the other players were taken to a T3 game....with only our T1 sets...So...yeah...we were kinda useless to our teams lol.
In other words...:
Was playing T1 lockdown just fine for a bit, nothing unusual here. A glitch happens in the next game and our costumes are being shown(Not a big deal, but I figure it might been related to the next glitch.), but it's still a T1 game. Hit played again. The next game we're in a T3 game, even though our T1 sets were the only sets marked for PvP.
I've run into that bug before. As a workaround, don't wear any high-star costume armor in your PVP sets (especially as it isn't supposed to show up in LD games anyway).