to be clear here is the post about them changing it due to “unfortunate behaviors”. To be fair I dont know what rule it would be breaking, but if it had enough to force them to change the behavior and not change the behaviors of the other battlegrounds is strange.
If they would put it under a rule it would most likely be this.
Cheating
You are responsible for how you and your account are represented in the game world. Cheating in any fashion will result in immediate action. Using third-party programs to automate any facet of the game, exploiting bugs, or engaging in any activity that grants an unfair advantage is considered cheating.