Why is the annual report of US stocks advanced?

Announcing the annual report in advance means that the company is ready for major planning before and after. It was obvious before the overall performance of the annual report was announced; One month before the publication of the annual report, the additional income of CSI 300 will be relatively released during the period of 1 to 3 months after the publication, especially in the month after the publication of the annual report, and stable additional income can be realized every year.