Granted in con job arcee did mention to bulkhead that "bots do change".

 

Breakdown was close to being a turncoat... but in the end he chose to attack Bulkhead despite saving his hide.

Supposedly in the next episode, Starscream tries to join the Autobots. If so, there's a possibility for Breakdown to follow him. Perhaps if they keep that ploy running long enough, Breakdown realizes that the 'Cons aren't worth fighting alongside. Then, when Starscream makes his ploy apparent, Breakdown stays sided with the 'Bots.

Again... sooooo doubt Starscream would be trusted on the Autobot team, let alone become a permanent turncoat. He's not Armada Starscream... that was the only Scream that had the appropriate change of heart.