The EOL dates for the different versions should be updated as agree in the [DISCUSS] Releases after 4.0 email thread.
4.0: Fully supported until April 2023 and high severity bugs until
April 2024 (2 year full, 1 year bugfix)
3.11: Fully supported until April 2022 and high severity bugs until
April 2023 (1 year full, 1 year bugfix).
3.0: Supported for high severity correctness/performance bugs until
April 2022 (1 year bugfix)
2.2+2.1: EOL immediately.