There are only 3 of us on the rota. So we don’t have the problem.
It’s a good question, I guess it depends on how your payroll department collect the data, and apply the rules.
I can see that if someone is long term sick or on leave for several weeks you could drop to 1 in 3 over a 13 week reference period.
But when does the reference period start and is it reviewed for each months pay?
I seem to be asking more questions than giving answers.