Opening date announced
Perhaps via that splash page, a due date is projected. Generally it's marked by a season (spring 20never) to give a little wiggle-room.
Opening date delayed
Spring becomes summer, summer becomes fall, fall becomes winter. Nothing opens when projected. And that wishful splash page is never updated.
To help get the word out, "influencers" are given a free meal. They're sworn not to tweet about it just yet, which makes them all the more excited to tweet about it once they're let out of their cages.
Friends and family night
Sometimes combined with media night, the friends and family preview gives the staff a forgiving environment to work out the kinks, before opening their doors for real and spending three more months working out the kinks.
Initial rumblings from the media preview have been let out of the bag, the friends and family have told their friends and family, and trend-hopping foodies descend on the fresh meat.
The Yelp reviews roll in, trigger-happy bloggers fire off opinions, and a buzz begins to grow.