Hopefully
ERRIDS (The EUROCONTROL/NATO driven “European Regional Renegade Information Distribution System”) will help in preventing such confusion in the future. Trials on 15th September with a Lear simulating loss of communication and shortly thereafter a significant deviation from the flight planned route, hence qualifying as a potential threat, and involving Maastricht UAC, the NATO Research Unit NC3A, the National German Air Policing Cell and the NATO Air Ops. Centre were a success.
Here's a partial screenshot of the info displayed:
Not very clear but includes info from FPL (inc. endurance POB) present position, altitude, heading, all updated in real time, and all available to all concerned