FlapsOne
If you look at the Ryanair website which shows the earnings you will notice that the last sentance on the page says:
"all figures are grossed up earnings – i.e. basic pay and grossed up sector pay"
easyJet's site show's earnings for basic salary then gives figures for sector pay.
The figure quoted by Ryanair includes a grossed up sector pay which means they've taken the sector pay, added the tax that is paid on that sector pay and added the total to the gross basic earnings.
When you take out the sector pay and the tax that is paid on that out of Ryanair's salary quotes the figure is similar to that of easyJet's.
Also easyJet work a 6 day on 3 day off schedule from what I gather and this is carried through the entire schedule so in effect you know you're roster 6 months in advance.