They've fought and made up, and fought and made up over it plenty of times... but the news was always that Alissa and Logan kissed, while she was still with Jake.
However, Jake has now apparently revealed the truth, by writing a (now deleted) tweet to a fan:
"Yeah... and this time I'm not being silent... Alissa f***** my brother... that's why I kicked her out... oopsie I just told them the truth... I'm done being the 'bad guy'.
Neither Logan or Alissa have addressed the explosive tweet, however Alissa did tweet: "Wait what hahahaha" shortly after.
As for Jake ending his tweet with "Martinez & Alissa backstabbed me.." he is referring to the Martinez Twins who just announced that they have left Team 10 in a huge YouTube rant, that starts with, "Ok Jake, f*** you!"
Watch the video below: