You will need the Full Write Service Plans permission to perform this action.
Open the service plan that needs a change in type, then choose Actions > Edit plan in the upper right.
In the Edit Plan dialog, change the Type field to the new service type. A checkbox labeled Update type on future [current type] plans as well? will appear below the Type field. Check it if you want the change to also apply to future plans currently using the old type. Click Save to apply the change.
Important: Changing the service type will not affect any currently scheduled teams. They will remain on any updated plans even if they aren't part of the new service type configuration.