The train is formed of 2 units. It is not proving possible move the train or to silence numerous alarms in the leading cab since the air leak (which was a major leak between units). The air leak itself is now fixed.
There have been attempts to use various methods of last resort (Traction Interlock Switch / Emergency Bypass Switch) to override the brakes, without any success.
The units are also unable to uncouple to allow one of them to take passengers to a station (due to crewing arrangements there are sufficient drivers to do this).
It's all looking increasingly impossible. I must admit I can't think of a similar scenario involving 387s on GX since they've been in service on that side of GTR!