BA paypoint 4 shorthaul F/O. In an ordinary month £3600-3900 take home, however I make an extra voluntary contribution into the pension fund of about £300/month. If I didn't, it would add £180 (cos it would be taxed!) to the above. If I really wanted see my soul and needed the cash I could probably add a few more £hundred with some overtime.
The variation is due to doing a little less or a little more work from month to month which bidline permits. Also number of nights away/month (which can be between 2-15 though I'm normally somewhere in the middle). More nights away = more £ due allowances.
Wigster,
A fair chunk of this is made up from flying pay/downroute allowances, which are paid the month after. e.g. If I am on leave/days off for all of May, then my June pay would be about £2700, which would explain the variation you mention.