Ryanair is not a permanant 5/4 they can be used into day 6 numerous times during the year making it 6/3. I am sure any Ryanair guys will give us the details.
For the record Easyjet cannot roster you into day 6 but if there are delays on the last day and you go past midnight you can do this 3 times in the year before you are owed a day off. This is not very common.
I now know all my days off until Mar 09 (with exception of the random blocks). How many companies allow you to plan over a year in advance? Easyjet rostering is not without its faults but 5354 is the best pattern I have had.