A change takes effect from the week you make it — weeks already scored keep the targets they were scored against, so moving climbing from 2 to 3 does not go back and unmake every week you hit 2. Calories are a daily ceiling, steps a daily floor. Leeway is how far over the ceiling still counts as hitting it — 2,000 with 100 leeway means anything up to 2,100 passes. Cycling, climbing and gym are how many days a week you want to hit. "Good week" is how many of those five a week must meet to count toward the streak — setting an activity target to 0 switches it off entirely.