I believe that I can answer the question with some authority since I have taken a group to Hedo every June since 2006 (next trip is June 22-29) and simply state that early summer works best for our group/Krewe due to great weather, other compatible groups there at the same time, manageable number of guests (not so many that wait times or sell outs occur but not so few people that there is no energy throughout the resort).
Crowds, at least my weeks, have been great. About 70-90% occupancy but I am not aware of any sellouts during the summer months.
Bugs? In eight prior trips, I only recall bugs being an issue one time when there was no wind after sunset and some people got bit by no-see-ums and mosquitos. I have never experienced any problems like this around the pools and away from the bushes and grasses.
Early summer is slightly different than later summer due to the building hurricane season (rainy season) which is mid June to late October. I have been to Jamaica during this time and it is a little hotter and more humid but not unbearable when you are in the pool most of the time or used to a tropical climate.
Just my experiences and observations.....
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