In article .com,
spotter wrote:
Does 346 belong to train 311?

This question is like "does [car #] 346 belong to the 8:36 from Epping?"
in that "train 311" is an timetable ID. Different physical trains [1]
make up that service on different days.

[1] Lets skip some of the detail here.

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RIP Morph (1977-2005)