With this feature, you'll be able to select the service type at the work order's fulfillment stage. This includes one-time service, maintenance plans, and the ability to change back and forth.
In the service order, click the hyperlinked service type under the service description column
A pop up will show the available maintenance plans for the asset and "One-time service".
Select the maintenance plan/task and it will change in the work order! The service can be changed back and forth as needed