well if you divide 10,000 extra seats by 189, the seats on a B738, your answer is 53 extra flights. So, if as lbaspotter says, its 10,000 over 6 months that's roughly one extra flight every 3 days , so maybe a w leg every 2 or 3 days?? I hadn't worked out the difference if a 752 was to be used as I'm not sure on the seat numbers but just very quickly if a 752 was 230 seats the difference would be 41, 41 x 180 days would be 7,380 seats so 'w' legs might be more likely?
The same would apply to Ryanair as 10,000 extra seats has been mentioned for them too, the only difference being we know they'd be B738s