The changes in that plan are relected immediately when you click Save and Publish in both the web components, and the GraphQL API.
This could potentially cause pricing issues for you or your users. See the Pricing and packaging section.
This field is not currently fully supported, and should always be set to
"latest", or left as the default.
The product ID is located in the URL when editing a product in Plan Builder:
Your plan ID is located in the sidebar of the Plan Builder, after clicking on a plan:
Your plan ID is located in the sidebar of the Plan Builder, after clicking on a feature: