I've never had a big problem with mosquitoes at all, in any season. Occasionally one may need a bit of repellent when having dinner, but overall it's not a problem. I only use natural insect repellent spray very lightly if needed, as my aversion to chemical repellents is even stronger than my aversion to the occasional little mosquito bite.
The resort must handle the mosquito problem well, because most of the time I never even notice anything.