Not for the last couple of days at least - they are full trains of aggregate hoppers - have seen them with my own eyes!
Are you sure you are seeing those particular moves?
RTT definitely shows them both running as class
0 (light engine moves) both yesterday...
Train information at Lewes between 1045 and 1530 on 03/08/2020. From Realtime Trains, an independent source of train running info for Great Britain.
www.realtimetrains.co.uk
...and today:
Train information at Lewes between 1045 and 1530 on 04/08/2020. From Realtime Trains, an independent source of train running info for Great Britain.
www.realtimetrains.co.uk
In addition to RTT, TOPS shows this afternoon's move running as
0Z71 (again, a light engine headcode):
66047 WBAE NEWHAVMD 880Z711Q03 F HITHRGDSG N
I know TOPS can sometimes be wrong due to human error, so as a final check, I looked at the
OTT signalling diagram for the Lewes area which also shows the train running as a class 0:
In my experience, it is extremely unusual for a Train Describer to incorrectly depict a
class 6 train as a light engine, so is it possible that you could have seen a different train?
MARK