There's a glimpse of the Amazon delivery dystopia on tiktok where the driver shows the monitoring camera and goes through the rules the system enforces. (Favourite ones: can't drink water while driving (even if stopped), can't touch centre console (e.g. for airconditioning, radio).)

Because of the delays due to rules (vehicle in park before unbuckle, seat belt buckled before moving, door shut), and the huge penalties for forgetting a rule even once, it is common for drivers to park and then run back and forth to the truck.

https://jalopnik.com/watch-an-amazon-driver-explain-the-comp...

> Seems to be at the discretion of the delivery person.

Historically: It's by section of the route. Each route is supposed to have designated walking or riding sections.

That might have changed recently though.