Every single year at the trade deadline, the position that sees the most players change teams is bullpen arms. There is not a contender that couldn't use more relief depth and given that relievers also usually don't come with prohibitive contracts even if they have team control. For the Atlanta Braves, that tendency seems to play right into their hands.
The bullpen arms the Braves are going to have readily available at the trade deadline are far from perfect. Raisel Iglesias is putting together arguably the worst season of his career, Pierce Johnson would fetch a nice return except Atlanta may prefer to keep him, and Rafael Montero is actively bad.