There is already ample discussion about this in the forum:
https://forum.fairphone.com/t/android-12-for-fp4/
https://forum.fairphone.com/t/fp4-security-updates-need-to-be-more-frequent/
Plus: Fairphone’s FAQ section: https://support.fairphone.com/hc/en-us/articles/4404656100753-FP4-Frequently-Asked-Questions-FAQ-