That early in the season there in not as many flights (ours don't start from MAN until the 25th!!) so I'm guessing Manos would only be able to buy limited blocks of seats from the airlines limiting their capacity at this early stage, when the rest of the flights kick in mid may there will be much more choice available. Also for the first few weeks of May Monarch and First Choice for example operate some of our flights so if booking for 14 days it may be necessary for a holidaymaker to travel out on one airline and come back on another, this for whatever reasons is usually avoided.