There used to be a loophole of the definition of a week. Max duty hours in a week are 55 on your roster, 60 if delayed at all. My record is 63 hours in 7 days however it wasn't counted as a week because it didn't start on a Monday!!!! 17 hours and 63 hours. Hmm, some difference there. Being rostered over 100 hours flying per calendar month isn't unusual and in addition there is positioning at all times of day and night, strange airfields, and the endless chatter on the radio as you head east.