This all has nothing to do with on-time performance and very little to do with staff annual leave.
The big problem here is crew shortage. Rumour from within says RYR are losing approx 150-200 pilots and cabin crew every couple of months. Hundreds of pilots, cc and engineers went to J2 since opening STN and BHX bases alone. Approx 400 are currently work their 3months notice as we speak.
Their policy of "everybody is replaceable, you want to leave? Get out" is unsustainable and big changes need to happen...fast.