via the Warhammer Community team
https://www.warhammer-community.com/2019/05/06/kill-team-elites-contents-focusgw-homepage-post-1/
"You’ll also notice a long list of new Commander options (some even wearing Terminator armour!), as well as powerful kill team operatives such as Aeldari Aspect Warriors and the Electro-Priests of the Adeptus Mechanicus. And, of course, there’s also a brand-new Faction in the form of the mighty Adeptus Custodes. How awesome (and utterly terrifying) is that?!"
"In addition to new open, narrative and matched play missions, there are also new rules for Sub-factions, enabling your kill teams to fight even more like their Warhammer 40,000 counterparts with Chapter Tactics, Legion Traits, Clan Kulturs and more besides."
