Now that we have a rough timeframe, is it too early to start speculating about the origin of the film's Aliens/Eggs?
By my estimation, they could be from LV-426 (as was the case in
Alien: Isolation), they could come from David/the Covenant, or (probably the most likely option) they could simply be discovered on whatever new world this film is (partially?) set on.
Spoiler
Since we seemingly have a crew of salvagers in this film, having them retrieve Eggs from (or get infected while investing) the long-since-abandoned Covenant could be neat.