As I sit and write this I can see a 769 stopped (westbound) just east of Chalk Pit Lane AHB crossing (Brockham, between Betchworth and Dorking) through the trees opposite my house, with a door light illuminated. It's been there for over 20 minutes. Its run to Gatwick was seemingly aborted at Redhill. Edit - still there with door light on, and 1V54 will be coming up behind it from Redhill soon. I wonder if it has failed, hit something or if there has been a landslip after all the rain. The line is on a moderate embankment there. Given the door light's illumination it would seem not to be a simple signal stop for a failed crossing, etc.