Forecasters, being "officers" were deemed not to need overtime, but work for the love of it.
There was however something called Long Hours Gratuity. To qualify, a forecaster had to exceed xx hours in a 6 week period, where xx was a large number. Here is the rub.
LHG came out of a different budget from travel and subsistence, so as a forecaster approached LHG qualification, someone from another base [say Leeming] was moved in "to take over your shifts for a few days".
The trick was, after being thus shafted, to be the man who went to Leeming to stop their team qualifying.
That way madness lies.