Find sample app attached. What I did:
Set the onChange on datepicker1 to:
Set(DateCalcTable,AddColumns(Table({ID:1},{ID:2},{ID:3},{ID:4},{ID:5},{ID:6},{ID:7},{ID:8},{ID:9},{ID:10},{ID:11},{ID:12},{ID:13},{ID:14},{ID:15},{ID:16},{ID:17},{ID:18},{ID:19},{ID:20}),"WeekDayCol",Weekday(DateAdd(DatePicker1.SelectedDate,ID,Days))));
Set(NewDate,DateAdd(DatePicker1.SelectedDate,Last(FirstN(Filter(DateCalcTable,WeekDayCol > 1 && WeekDayCol < 7),15)).ID,Days));
Set(resetDatePicker2, true);
Set(resetDatePicker2, false)Set the reset on DatePicker2 to:
resetDatePicker2
Set the default on DatePicker2 to
NewDate
