What does Skerrick actually block?
Nothing outright. It rations the whole app you pick, not one screen inside it. You get three minutes in Instagram per visit by default, and the clock runs whenever Instagram is in front, whether that is Reels, Stories or your DMs. Limiting the app is how it limits Reels, Shorts and For You. The app is never blocked or deleted, so a message still gets answered, inside the same minutes.