Unless the system has been updated that won’t work. Cornwall drivers can’t sign on Somerset ticket machines and vice versa. Hence when a BoS vehicle used to cover Dartmoor when Exeter was under Cornwall it used to have a ticket machine swap and track as a Cornish vehicle.
Exeter drivers now report to Taunton so Exeter buses have Somerset machines and plymouth buses have Cornish machines
Well if that's the case it has to be a three bus service.
One end sends out a bus on the first trip which returns on the third return.
The other end sends out two buses on the first and second trips which then return from the other end on the second and third trips.
In my view very unlikely to be Exeter sending out two buses with a 5 minute turnround at Plymouth while the Plymouth driver has over 4 hours in Exeter.
Much more likely to be one Exeter bus with three hours in Plymouth and two Plymouth buses with an hour and a quarter in Exeter.
No 5 minute turnrounds this way.
Can't say I've looked at the Exmoor route for reliability but if it only has 5 minutes in Ilfracombe I can see delays as likely on busy days.