Hi Vastra- We currently don't have an endpoint that schedules a ride in the way that you are describing. Uber is an on-demand service, but I can definitely see used case for that. Perhaps you can somehow build something that helps solve that scenario?
Vastra - you might also want to look into Iron.io's IronWorkers. You can schedule a future task (like making a request) for a specific time in the future and return a success / error response. I use it to schedule SMS messages.