I agree with captainsmiffy. I am sure ATC would like a heads up on aircraft about to commit. It would be interesting to know how many do each night in DXB. As I understand it you can commit without an EAT anyway if two independent runways are available etc which is the case most of the time at DXB.
The facts as they stand though are that we don't have to mention a thing until we " might" land below final reserve. The new ICAO directive is to call " Minimum Fuel". I would have thought endurance in minutes might be a useful piece of information as well?