Permission for users to create plans but not groups

I think I have worked it out!

According to the Microsoft graph API:

• Groups and teams share an ID so have 1:1 correspondence
• Groups and plans don't share an ID. The group object owns a PlannerGroup object which contains a list of plans owned by the group. https://docs.microsoft.com/en-us/graph/api/resources/plannergroup?view=graph-rest-1.0 . This means that they have a many:1 correspondence
• Standalone plans quietly create a group and give it ownership of a single plan. That group could potentially still own more plans in the future.

By creating a plan through Microsoft Teams, you can create a plan without needing permission to create a group just as the API would suggest. I am not sure if this is due to a recent update or not but it is now working for me.

You need to create a new tab in a channel within a team and select planner, then create a new plan. This will automatically give ownership of the plan to the group associated with your team (with the same id as your team).

I'm guessing this bypasses a stage where you would need group permissions or something. I have checked and I still don't have permission to create groups so that is a good sign. Either way, I'm glad it works.

James