All departures remain from T1, but who knew domestic arrivals are still into T3?
Arriving from Exeter you are directed by signs from T1 to T3 Domestic arrivals, where there are no staff, no baggage belt information. Then you exit into the T3 deserted forecourt. Unless you were familiar with the airport layout you wouldn't know where any facilities were. If anyone were meeting you, they'd probably expect you in T1 where you departed from.