OK another quirk:
When I did the test above I had my SP3 in the docking station. I removed it from the docking station and it lost contact with the wireless display adapter. Took several tries to get it reconnected and when it did the resolution was at 1366 X 768 again!
I had tried moving the SP3 back and forth from the docking station....(.that's ultimately what I want the wireless adapter for....when I'm on a conference call I want to take notes on the SP3 but retain the external display so I can look things up, etc.) Even before I found this thread and knew about the bt issue it was loosing connectivity with the adapter when I would move it from the dock or replace it. This is probably a totally different issue but somehow it seems to be connected.
Anyone here have the same issue?