Here is a link to figure the Age as Of:
Enter the date of birth, and the age as of date should be July 31, 2020. The age that appears is the age group the player will play in Spring 2020 and Fall 2020.
TSYFL Spring football is to get teams ready for Fall, where players and coaches find if players fit their position, need to be moved, or fill holes in weak spots, and ultimately recruiting players for need spots.
Therefore the "age as of date" is July 31, 2020. The Spring team has the opportunity to play together, much as high school Spring training is to evaluate and get players in place for Fall.
Teams and clubs should contact their Conference Director for information regarding the conference.
Season start dates and other dates will differ between conferences.