From FOX's 2017 film showcase:
LeonBrill: #AlienCovenant is gory, tense, and thrilling. Should be a return to form for the series. Wow.
LeonBrill: #AlienCovenant trailer screened.
So apparently they screened 15 minutes of footage, followed by the first trailer.
Fandango: Wow, we just watched the gnarliest 15 minutes (plus 1st trailer) for #AlienCovenant. Aliens busting out of body parts; super intense action!
ErikDavis: The #AlienCovenant stuff was crazy, bloody, gnarly & just plain badass. Multiple aliens, hang on to your stomachs - things get gory!
jhoffman: Just saw clips of ALIEN COVENANT. The ship is giant & flat, Danny McBride has a funny hat and also: EWWW (it's definitely ALIEN.)
Fandango: What's interesting about #AlienCovenant is that most of the space travelers this time are couples & colonists. And the aliens are crazy!
ErikDavis: They didn't say when the #AlienCovenant trailer was gonna drop, but let's say it ends w/ what is sure to go down as a classic shower scene