What is the summer of application cycles like?

I am planning on applying next year for admission to enter medical school in Fall 2021. I hope to take the MCAT in April/May. I plan on applying to 16-20 schools. How busy will I be with applications during that summer? Could I reasonably do any summer classes? I was considering doing Organic Chemistry II Lab and Biochemistry Lab during that summer (to save time to study for the MCAT during my Spring 2020 semester).
Source: Student Doctor Network - Category: Universities & Medical Training Authors: Tags: Pre-Medical - MD Source Type: forums