First Concorde route was Heathrow-Bahrain.
I believe the accel point was over the Adriatic, and from then on M2.0 all the way across Saudi and down the Gulf. Flight time about 4 hours.
Dubai could be quite a successful route; plenty of high-yield traffic, but to build the market would have to be a daily service to compete with Emirates/BA. With only 5 aircraft, how would SRB propose to service JFK and DXB daily?
Also, would the Saudi's allow supersonic overflight of their (admittedly, empty) territory?