It's worth noting that if Flybe were able to allow you to operate lates one day into earlies the next then they would, provided it was safe which is questionable at best.
Unfortunately the CAA deem this to be unsuitable and CAP371 means that you can't have lates into earlies. This is not Flybe's doing so its not so fair to gripe at them.
It is a fact that to be rostered lates going to earlies in order to maximise days off requires a massive increase in staff and with margins in the industry so tight, I guess it is a cost that simply cannot be born.