Hey! I am a current DrPH student and thought I could lend some insights since I relied on this forum heavily last year.
I heard back from one school in late Dec about an interview (my top choice and current program), and the other two schools the first and second weeks of February. I heard back about acceptances the March 13-14th from all three schools. All three programs offered scholarships and job offers in March as well.
I did get rejected from Harvard and that was sent on Feb 18th.
Overall, by mid-Feb you should start hearing back so no need to stress before then I wasted a LOT of time compulsively checking this forum.
Good luck ya'll!