Hi Bce1 and welcome to PPRuNe.
We have about a dozen of each senior rank, although those figures are complicated by the number of jobshare roles - meaning that there are a dozen jobs but about 15 people.
The rosters are such that you tend to work like fury for a while, and then suddenly find yourself on a combination of standby/leave/training and doing not very much. This system (I believe it was perfected by various Armed Forces) is a variant of the process known as "Hurry Up and Do Nothing" and means that for periods of time you wake up at 07:00 and the dog gets an early walk and for other periods, you sleep as much as the dog does!
Glad you're enjoying our service, but commiserations on the every two months thing: Make sure you're earning FF points!