I think your clues are incorrect - specifically clues 1 and 5.
Clue 5 is wrong because, having checked the routing guide, the only permitted routes are the shortest one (via Oakham, Leicester and Nuneaton), routes within three miles of the shortest (no new routes added), through trains (IE the XC services from Stansted, already stated as valid by shortest route), or routes on map BP, which includes only the Peterborough - Oakham - Leicester - Nuneaton - Birmingham route.
Clue 1 is wrong because I do not think that theres any Voyagers or HSTs booked to work the Stansted to Birmingham services.
Anyway, on with the show!
- This journey starts at a 2 platform station
- This journey ends at a larger station
- This journey is run using a single class of EMU under normal circumstances
- We pass at least one interchange to at least one other mode of transport.
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- This station has signs indicating it serves another, larger place.