There is a tool designed to allow instructors to manage the conversion of Face-to-Face activities to Sessions (Instructor Led Training) one at a time. It runs a background job but is typically very quick to complete. It is built into the Sessions activity itself and can be accessed inside the activity instance once created.
Steps to migrate an existing Face-to-Face instance to a Session instance.
Inside a course, create a new Session activity instance with a name and click save and display. Once it loads the activity there is a button to migrate Face-to-Face to this new Sessions activity.
It brings up a chooser with the list of each Face-to-Face instance that has not been converted and lets you choose which one you want to convert.
You can choose to hide the Face-to-Face activity once it is converted or leave it open for use for now. Once you really start using the Sessions activity, hiding the source activity will be the quickest and simplest way to proceed.
Once it finishes the conversion, the newly created details in the Sessions activity will be displayed.
All the tracks and the attendee information will be imported into the new Sessions activity. You can see it and review the details and start making adjustments here.