Persistent little buggers aren't they?
I don't know if this will help you:
My kids therapist had me look at their behaviors a bit differently They were normal teen behaviors
My X was the one acting like a teenager/toddler and not his age.
I found it easier to deal with them when I was thinking this is a NORMAL stage of development for them. When I was thinking I had a mini -PDXH on my hands, I was beside myself. Chastising all of my parenting up till that point. And taking the focus off them to X. I needed to stay focused on the kid.. and knowing that this was close to normal for teens helped me to deal with it.
Doesn't mean you let it continue, But I am willing to bet there are suggestions listed on a parenting teens site or 50 that have suggestions on dealing with this behavior in teens. Therapist told me that they will revert to what worked when they were little to get what they want. This held true with all of my kids (varying degrees) If one yelled and thru a temper tantrum.. she yelled and thru a bigger temper tantrum. One DD would do her best to wear me down so that I would say yes just to get her to shut up about it... it was 20 times worse as a teen.
having the therapist tell me this... helped me to have more patience and to stand my ground.