The Cambridgeshire & Peterborough Combined Authority has issued a contract to local operator A2B to operate additional journeys on the Cambridge-Ely-Littleport service 9. A recent post here had noted that Stagecoach will be cutting back on the number of journeys they operate on this route with effect from next Monday, 15 April. The Combined Authority has arranged for three additional services in both directions to be added to the timetable.
The Combined Authority announcement, which includes a complete list of departures for both operators, as well as ticketing arrangements, is available on its website.
Cambridge Area Bus Users 
That explains the A2B bus that passed myself and a friend of mine last Thursday evening (4/4/2024) near my house in Ely, obviously on a route learning trip.
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