So does the monitoring system actually send current status between engine status changes?
The impression I got from earlier posts here was no...that the only time they actually report data is when the engines have significant mode changes and/or there is some parameter that goes beyond a critical threshold.
If my impression is correct, then it again would be consistent with the original WSJ reporting. They know the engines were running and stayed running but don't know anything about their condition or power status, etc. That then gives them the 4-5 hours of continuous flying at some speed, altitude and direction.