Interestingly, when the Spanish services from Exeter and Norwich, were stopped, temporarily, with the E95 after Christmas, Flybe continued the Exeter-Norwich service with the Dash. I must admit when I have flown the route the loads are full or nearly full. Also, the fares, if booked early, are cheap as it is a start up route.
Another point is that the hinterland for this route is increased because there is no direct competition for Norwich, as Luton and Stansted don’t fly to Exeter.