Star Trek: 12 Things You Missed From The Discovery Season 4 Trailer

Tilly appears in the previously mentioned 32nd-century space suit, conducting an evacuation of the upside Starlfeet starship.

This ship (or space station or other facility) appears to be distinguished by orange-red panels on the bulkheads and signage, a new look for the previously sterile white look of far future Starfleet.

In this shot, Tilly is aiding a non-human officer wearing the gray Starfleet uniform featuring the slash of division color on the right side which is apparently still in use, despite the USS Discovery officers appearing in a new, more colorful variant... more on that in a bit.

That alien, by the way, is a Shlerm, one of the fifty aliens designed by makeup artist Joel Harlow for Star Trek Beyond (which somehow lost Best Makeup to Suicide Squad at the 2016 Academy Awards). To our knowledge, this is the first appearance of an alien created specifically for a Kelvin Timeline movie showing up in the Prime Universe, perhaps an indication that Discovery, Lower Decks, and Picard all now have access to Paramount's feature film assets following the re-merger of Viacom and CBS.

Another alien in Starfleet garb which appears during the evacuation is a Lurian, Morn's species from Star Trek: Deep Space Nine which previously appeared in season 2's "That Hope is You".