When you're creating or attaching a new contract in a Shoot, you'll see that the [[payment_schedule]] and [[package]] variables are blank. There's a good reason for this!
A contract can only reference a package and payment schedule that are used at the time of booking. If you create a contract outside of a Booking Proposal, Sprout Studio doesn't know which order or invoice you are referencing. Because of this, we don't know what info to add to the contract.
This logic also extends to the contract preview option in a Booking Proposal. The contract preview only shows information that we know. These variables do work when you use them in the Booking Proposal contract once your client selects a package in their proposal.