Hi Sallie - flora chiming in!
My experience when first coming off Tapazole (February 2016) seems somewhat similar to yours in the beginning - my TSH declined for the first couple of bloodlabs, and then began to rise back up (which must mean that my hormone levels rose at first, and then dropped - my primary care doctor here monitors my TSH). In my case, it was because I was slipping “hypo”. In fact, doctor had been pretty sure that I was going hypo, over the previous many months, because even though he was gradually reducing my Tapazole dose, my TSH would go “up”. We began replacement hormone last July (Synthroid), and the light at the end of the tunnel has been getting brighter and brighter ever since. This may not be the explanation for how your thyroid is behaving, though. As Kimberly once said, when a doctor has seen one Graves patient, he's seen one Graves patient
All the best to you and your doctor in figuring things out - it takes time (way longer than we would like), but we get there, sooner or later! Drop back in and keep us posted,