Calsky has an amateur generated TLE for the train and will do predictions. Use Spacecom ID 99201. The TLEs are currently over a day old and the orbits will be evolving quite rapidly as each spacecraft uses its ion thruster to move to its operational configuration. The prospect of 12,000 of these things in LEO is indeed a concern for astronomers although there will be long periods when they are not illuminated.
It was cloudy in Essex last night but John Mason had clear skies for the low pass at 22:16 UTC and didn’t see anything.
Epoch is 24. May 2019 Starlink Trail
1 99201U 19894A 19144.95562291 .00000000 00000-0 50000-4 0 02
2 99201 53.0084 171.3414 0001000 0.0000 72.1720 15.40507866 06