I'm setting up in-app purchases in App Store connect. What we would like if for people to purchase a subscription but not be billed until January 1st,2020. I've noticed I can give people a free period that is not bound to a date but to a range (2 weeks, 1 month, 1 year, etc).
Is there any way to set up a subscription that starts running on a specific date in the future?
Unfortunately, no. If users purchase a subscription, even free trial period, you have to provide premium functionality in your app.
If you are planning to start providing premium functionality since January 1st, you should offer subscriptions only starting that date.