Ryanair has been and still is using UK based agencies to setup their very questionable pay-per-hour ltd's that place pilots predominantly in continental Europe where they live and work under a totally borderline tax&social status.
These setups are poisoning and distorting the market causing great damage mainly to the airlines that have to compete with such medieval employment methods.
The main victims are of course the more local and less cash-rich airlines of sounthern Europe where in less than a decade competition has been virtually eliminated and their airports are full of blue/yellow 737's with their contracted crews.