As we progress through the Summer semester, we'd like to highlight a few key dates for Drupal in 2021 and 2022 to clear up any confusion.
Drupal 8 support ends on 2 November 2021:
Drupal.org: Drupal 9 Release Date and What it Means for Drupal 8
Drupal 8 is dependent on Symfony 3, and Symfony 3's end of life is November 2021. Consequently, Drupal 8 support will end in November 2, 2021. A long-term-support (LTS) Drupal 8.9 minor release was released alongside Drupal 9 and will be supported until November 2021
Drupal 7 support ends on 28 November 2022:
Drupal.org: Drupal 9 Release Date and What it Means for Drupal 7
[...] in light of the impact of COVID-19 on our community, we have now extended Drupal 7's support and moved the end-of-life date to November 28, 2022. (Drupal 8 is still end-of-life in November 2021.)
Other helpful documentation:
Using composer to upgrade to Drupal 9
Expect more updates in the future for campus resources in order to help the community through this transition.