shurely £3000 take per month equates to about £36K pa.? Or are you at our Mars base where the year is longer?
Seriously, the current situation is that 70% of sector pay is untaxed, and the rest is fully taxed, like your salary.
This means that for each sector, you get £8.40 +£2.16 = £10.56.
You fly close to 850-900 hrs per year, you work out an average sector time and this should give you a rough estimate.
Over the average year this would work out to be between £6000 - £9500 net; the upper limit only being possible if ALL your sectors were less than 1hr flying time = never gonna happen.
But payments for Days Off bought make quite a difference, too.