Query: timetable feed listing active RIDs for specific routes

[Mas Gol]

Dear Team,
I hope you are well.

I am currently working with real-time rail data and I would like to ask whether there is a timetable dataset or feed that provides a daily list of train services (by journey/RID).

In particular, I am trying to obtain a list of RIDs that are active for a given route on a specific day (for example, services running today or tomorrow from Weymouth to London Waterloo). Is there an existing timetable or schedule feed that publishes the set of planned services (and their RIDs) each day, for example overnight, similar to a daily timetable export?

If this is available, could you please point me to the relevant dataset, documentation, or best practice for deriving this list?

Many thanks for your help.

Kind regards,
Mas