Although there hasn't been anything in the way of official confirmation, if the cast of the actual show says it then there's a better-than-decent chance it's accurate.
According to a recent interview with Decider, none other than Henry Winkler, AKA The Fonz, AKA Barry Zuckerkorn, has said that the new season of Arrested Development is returning in "midsummer", which we're taking to assume June or July?
Netflix, of course, are known to shift and change release dates without much in the way of notice to viewers. For example, the Monty Python filmography was originally supposed to arrive on the streaming service in February of this year, but only turned up a couple of weeks ago. Likewise, The Punisher's release date was pushed back over a mass shooting incident that took place on the weekend of its intended release.
So, if we can expect Arrested Development's return in the coming months, how about a trailer then?