Just because you can pre-order the Aeldari codex now for 40k, it doesn't mean that Games Workshop is done with previews for them. The updated figures for the faction aren't the only ones they're getting, as the Corsairs from Kill Team: Nachmund are also getting rules to be used in the bigger-sized game. Get a look at them here.
From the article:
Beyond all the big, bright new Guardians, Aspect warriors, and Avatars, certain Aeldari have been up to some more sneaky stuff in this season of Warhammer 40,000. For instance, there’s a buccaneering band of Aeldari Corsairs getting ready to clash with Chaos Space Marine Legionaries in Kill Team: Nachmund.