RHiNo
I am at a airline whose rival is Ryanair.
Mayday calls are made according to our ops manual when we believe we will land below Final reserve fuel. We do not wait till we are at that figure.
Personally I find when it hits the fan in these places it is sensible to be proactive. If I was anywhere near landing with FRF in these circumstances I would declare a mayday.
If I was a Madrid controller.....I would keep my head down !