When creating an invoice for a project payment, you can include more than one payment term and even change order payments of the same project.
The process to create the invoice is the same as before: either from the Details > Payments tab in the Project Details view, the Accounts > Clients page, or the Billing > Invoices page.
Check out this article for more details.
In the invoice creation modal, you will see the following additional options:
A plus icon below the row for the next term to add more terms from the project, and change order payments.
A dropdown next to the payment term to select from the various payment terms.
A minus icon to delete any payment term.

