What We Learned From the Trailer

The show is about a team of five enhanced clones, who are extremely capable fighters with different sets of skills. The problem is, these clones can think for themselves, unlike their foot soldier counterparts.

Timeline wise, this takes place early on in the Empire, before the development of Stormtroopers. We see a mix of late Republic and early Empire technology and architecture, as well as the presence of clones rather than stormtroopers, we also see a familiar face: Grand Moff Tarkin.

The Grand Moff was one of the least likable figures in the entire original trilogy, despite dying along with the Death Star at the end of A New Hope. So, we can assume this takes place post-Revenge of the Sith, but pre-Rogue One.

And, while he doesn't appear, it's assume you can see Darth Vader right after that whole high ground incident.