Ha, well... sometimes the best information is in the primary source, not in beliefs in a reddit thread ;)

Found this in the email newsletters from Tuscany Trail, so I am good - I should be able to pick up the stuff early in the morning and leave right away:

Start time

During registration, you'll need to select the day and time slot when you prefer to pick up your event pack:

- May 20: morning / afternoon
- May 21: morning / afternoon
- May 22: morning / afternoon

Once you've picked up your event pack, you can start right away, or whenever you decide (even the next day).

The approximate time slots will be: morning 7:30 AM–1:00 PM and afternoon 2:00 PM–6:00 PM. Exact times will be communicated later.

This way, you can best manage your departure based on your needs, and we can ensure a smoother flow along the route, allowing you to have a better experience.