I have 30-40 traps out for the last 3 years.
Last year I caught 20, most were caught in May and Jun, then it drops off to 1 or 2 from July to Sept. Those late swarms are often smaller, some the size of a baseball. Just not enough time to get them to size for the winter. The smaller the hive the more you have to mess with it. Most of my winter losses are those late swarms.
July - Sept wax moths increase every day until a freeze, I treat with BT but have some pollen left in some comb and the wax moths get one or two of my traps.
For those reasons I will be pulling my traps in July. I will still leave a few around my apiary.