There are presently a large number of short formations. Yesterday was especially bad. The reasons that I have been given for this are:
- Some additional services were running
- Some trains out of use due to wheel flats?
- Extra trains have gone away to the works since Blackpool closed
I don't know how accurate these are. In a week's time there will need to be extra units resourced on weekdays for the Bishop line and the half-hourly Ribble Valley line service to Blackburn too. Other changes mostly affect Sundays - and on Sundays the number of extra units required in service is probably quite large.
I thought the Calder Vale extension was off-peak only meaning it doesn't need any additional units over what would be used on Calder Vale at peak times.
This was my understanding too. There are only 6 weekday services to Manchester Oxford Road.