You don't seem to be using terms very clearly.
A district event is a competition, about 40 teams, that takes place in a district (which a team in Iowa would not be in). The district championship (or "states" if Michigan) is a competition for which teams are invited based on accrued points. I do not know who is notified, but at least for Michigan, a publicly-available spreadsheet shows how you are ranking.
From Regionals (competitions not in districts) and district champs, teams that qualify then are invited to the Championship ("worlds" or "nationals"
). Again, I don't know who exactly is notified, but it's usually obvious if you are invited.
If you are going to Championship on the lottery, that's another kettle of fish.
Edit: What team are you with?