Is Meng Haoran's Spring Dawn about early spring or late spring?

Sleeping sickness in spring unconsciously broke the morning, and the chirping of birds disturbed my sleep. How many flowers fall after a stormy night. The poet Meng Haoran's "Spring Dawn" should be written in late autumn. At that time, the summer solstice was not over, the weather was often changeable, and the flowers in early spring were not easy to wither. Only at the flowering stage will the flowers die and the flowers will not be weathered, so this time is as big as late spring! Birds are singing, and people don't know it's dawn when they are sleepy in spring. It's time to get up!