Changing Plan Start Date?

I joined today and it wanted me to start today but I’m a bit fatigued and I’d like to be fresh for a ramp test next week

Any way I can switch the start date?

If you are using plan builder you are prompted to set the start date at about step three or four. Here you can pick whatever date you want, both in the past or in the future. Are you building your own plan you can click the date on your calendar you want to start.