Her defense is beginning to become clear...
Think back to her second answer on the stand, "the simple answer is 'self defense'". Many posters had different theories as to her answer, most specifically "the simple answer" and many debated on what the underlying meaning to that pretense was. Now, that we know JA so much better, we can be certain her answer was very much a clue to the end of her testimony and why she killed Travis.
She is going to say she went to AZ to guard between Travis and some child. She even went so far as to go out of her way to give up her body (clean shaven even) to him. so protect some child that she will name in this testimony (got to make it believable). She'll say he was becoming less and less satisfied by her 'pretending to be a child'; therefore she was no longer able to detour his pedophile sexual appetite. She'll say she found evidence that he was about to 'pounce' on his prey (who she will name) and she had no other choice than to kill him to protect all the children.
This is the 'underlying meaning' to the "the simple answer"...it was her simple answer to the 'real' answer that is now being explained in testimony.