When did the ambush start?

The dive begins from summer to the third Geng day in the future. Until the end of the day before the second Geng Day after beginning of autumn. The dog days are divided into early days, middle days and late days. The initial period starts from summer to the third Geng Day in the future, the middle period starts from the fourth Geng Day, and the end period starts from the first Geng Day after beginning of autumn. The first and last days are 10 days, and the middle day may be 10 days, or it may be 20 days, because the third Geng day after the summer solstice solar term appears sooner or later.

Introduction to dog days:

Entering an ambush means entering the dog days. Three volts is divided into initial, intermediate and final volts, which is the hottest period of the year. The dog days appear in the Gregorian calendar from mid-July to mid-August every year, and its climatic characteristics are high temperature, low pressure, high humidity and low wind speed. "Fu" means being forced to hide underground, and the date of three volts is determined by the date of solar terms in the dry calendar and the date of the dry calendar. Because every Geng day is 10 days apart, the stipulated time of the first day and the last day is 10 days.