No its a light loco, not a passenger service. The times I have indicate 2 diagrams. One stopping at West Brompton, and the other running direct, calling only at Kenny O. Either of the diagrams could run, but I think there is only 1 running per day. Also, they both run as required so may not show up at all.
The times at ealing are either 1030, 1150 and 1430 (for non stop diagram) or 1100 and 1410 (for stopping diagram). Your best bet is in the afternoon, 1400-1430-ish and it should show up.
I imagine when a 171 is freed up, these diagrams may work again with a DMU?