Only if Amazon have off-line ultra HD. LTE is not reliable at some location and insider building. I would do hard wired streaming at home or off-line on the road. Doing away from MQA is good if Amazon can do 192/24 or at least 96/24. My Oppo HA-1 and 105D can't take MQA.
Logged into Amazon Music on Node2i,  HD option shows up as menu item. When you click on it it asks you to sign up
Aurender says they are in contact with Amazon and will update in the coming weeks.