That certainly sounds like ARFID, especially only eating foods packaged a certain way or from a certain brand! And it makes me very happy to hear how much progress you and your child have been able to make - congratulations on that! Patience is key, absolutely. Some say hypnotism can help - not sure, I’ve only ever tried when I was much younger and it didn’t work for me - but other than that the general approach is just very very gradual exposure. So your patience is absolutely essential :)!! If only all parents had it