Mic-Nificent
I didn't eat nobody
New Mutants is out in April, and they've apparently been testing it for a few weeks now(if Twitter is to be believed). It could easily be either one.
Also, all of us (including myself) need to keep in mind test screenings are not always indicative of the final product. There have been bad films with good test screens and good films with bad test screens. All depends on the edit they decide to go with.
There's also a huge difference between test screenings and fan screenings.
Fan screenings are usually where they bring in a bunch of fans and friends of people who made the movie. Those are always positive. a prime example would be the ones for Fan4stic and Green Lantern.
Test screenings are usually a mix of fans and casual movie goers. You get a good mix of people who are predisposed to liking the film and just random people. Usually when a film tests well during those screenings they go with the edit they've shown. When reaction to those screenings are mixed you either don't hear about them or you hear about reshoots to add or take away things from the film (examples being Dr Strange adding more humor and Thor: The Dark World adding more Loki)