When you go to upgrade your workspace, you may notice that the number of makers is calculated for you. This is based on the number of makers you currently have within your workspace.
As the admin, you're able to navigate to your workspace through coda.io/docs and modify permissions of collaborators on the right-hand side. You need to click on your workspace name in the left panel for the Members list to appear.
Another way to get here is through the payment processing page.
Do you need to add or remove makers within the billing period? No problem! You can do so and the change will be reflected within your next bill.
One last note: If you change permissions of a maker within your workspace to editor, they will no longer be able to make their own docs. Any docs they previously created will become read-only unless you transfer ownership of those docs to another doc maker. See how to transfer doc ownership here.