personally i see several options as of now:
a) aquaman 2 jan-june 2022, blue beetle june 2022, flash september 2022, universe resets, dcu starts in a new timeline
b) flash september 2022, aquaman dec 2022-june 2023, blue beetle june 2023, dcu starts in a new timeline
both are fine to me as i dont see the dceu being revisited in the future, but for now im going with a until there is evidence found in either blue beetle or aquaman that puts them solidly in 2023, its just cleaner to me to have everything end with the reset in the flash, but aquaman appearing in the flash post-credits says to me either way can be valid