Well for the first time last month I hit £1,000 in allowances at LGW. I have been here just coming up to a year so it is possible! THo this month will be nearer the £750-800 mark.
Tax wise...the overtime rates are taxed per normal basic rate.
Hourly flight pay is a bit more complicated....out of the £2.32 18% of this is taxed at the normal rate. For example 18% of £2.32 is 0.471pence. So it is this tiny tiny tiny amount which is applied.
The overnight allowance is completely tax free. We are much better with this than the LHR deal.