I'm interested in railfreight in the North West.
Freightliner indicate that there are up to "20 services a day" using their Old Trafford Manchester terminal. Recent reports suggest that at least one of these is to Tilbury. I also understand there are liner services to Southampton and Felixtowe. Assuming 2 trains per hour per direction for each of these, this equals around 12 services. Together with additional services to and from Crewe (remarshalled from through WCML services, or stored rolling stock?) this would seem to summarise the operations pattern.
Am I missing or misinterpreting anything with these assumptions?
Someone will be along with a more informative reply on the precise patterns.
I would imagine the precise composition of diagrams is at the whim of the patterns of ships and so subject to ad hoc changes.
You can also check using RTT the pattern of services on a given day. The big one you are missing in your list is London Gateway, which yesterday had 4 each way to Trafford Park. There's also a daily Daventry.
I think 'up to' is doing a lot of heavy lifting here. Yesterday there were 29 liner workings (I don't know whether Freightliner, DB, GBRf, DRS) to and from the various Trafford Park terminals. So '20 services a day' is either a low estimate of to and from workings, or a low bid on single direction.