I separate film canon into 5 lines of continuity:
1. The Prometheus series, leading presumably to Alien.
2. The Alien series, the original 4-part saga.
3. The AlienS series: Alien, Aliens, Alien5 (it'll happen!).
4. The AVPs, which counts all A&P films up to 2007 as canon.
5. The Predator series.
So Covenant doesn't really change anything for me. I just file it in the appropriate section.