[Sheestgag]

HA has more than one face. What I am reading from your post is that you are dealing with Fear Agression. All the vocal warnings, defensive stance, the mohawk, growling at you & backing up. (So not Bulldog behaviour!)

I would bet that this dog has been abused and not socialized. (tied to an old bumper kinda explains that!!) Once a dog realizes that it can use aggression to achieve a goal - (in this case keeping the human away) - the dog will gradually access that aggressive behaviour more and more frequently and find security in that.

The esculation is that once the dog bites out of fear and realizes that the effect is greater than the warning, the access to biting to achieve a goal will be more readily accessed - then you have a serious problem.

8 months is still young and with some serious and committed effort and the correct training, this problem can be reversed. Expose her to her fears so that she can overcome them. Do not enforce her negative behaviour - enforce only her positive behaviour.

I need to close by saying that if the HA increases, you must do the responsible thing and have her put to sleep. (HA Bulldogs must not be relocated or rehomed - especially where fear is the base.)

Good luck