Mmmmm I'm unsure as to just how realistic this rumour may be.
If true then I would be amazed. Surely Exeter Airport run the risk of losing all the new Flybe services that they have just aquired. Realistically I cannot see them wanting to severely pee off their based operator who has taken the considerable risk of investing in the new routes.
Equally it would surely not be economic for Easy to have 2 bases so close together. The only reason for them to move out of Bristol is if the new Flybe services have really dented their projected booking figures, which I find unlikely as the scheduled Flybe services from EXT to ALC/AGP seem to have caused a minor reduction in charter services at EXT. The likes of MYT have chosen to route some ALCEXT flights via SOU to combine pax loads. I would deduce from this that Flybe's flights are simply replacing those of the current charter airlines with a few more seats available.
We'll see what happens but I would be staggered if this is true!