2 Car Class 171 Diagrams

Trying to track down a couple of elusive SR DMUs.
From what I can glean there are three 2 car unit digrams on the Marshlink Route with one spare at Eastbourne.
The rest are therefore used on the Uckfield Line but most of these are 4 car diagrams. When do the 2 cars come out? Which Peak time diagrams get more units?

Cheers

Weekdays have a number of Uckfield stock circuits/diagrams formed from 2 coach units coupled with others. There is a 2+2 formation in the morning which becomes a 2+2+2 in the evening; a 2+4+2; a 2+4+4 etc.

Weekends on the Uckfield Line are generally 4 coach formations although sometimes 2x 2 coach units get used on a diagram.

On Sundays there will usually be at least one 2 coach unit on its own on the Uckfield route. This is now the only day of the week where this will routinely occur, because on Sundays the trains shuttle only as far north as Oxted, and there is remarkably little demand. It is not generally practical to send a 2 coach unit into London, although it used to happen pre-May 2018.

D1023 said:

From what I can glean there are three 2 car unit digrams on the Marshlink Route with one spare at Eastbourne.

Click to expand...

Indeed, three 2 car units operate the daily Eastbourne-Ashford-Eastbourne services, with the fourth unit used on the morning/evening peak Rye shuttle diagrams, berthed at St Leonards Depot when not in use. However, from next Sunday (19/05), the Rye shuttle will be extended to operate all day on weekends only. It's good that they're increasing capacity on the Marshlink over weekend periods, but, with 171 reliability at an all-time low, I can see this new service throwing up some issues!