I do not know if this achieves what you want.
// Current state of the event ('active', 'locked' or 'deleted') 'locked'
// indicates that start_at/end_at cannot be changed (though the event could be
// deleted). Normally only reservations or time slots with reservations are
// locked (see the Appointment Groups API)
This means that the event can still be deleted and are is some way "editable".
Best Regards,
Ana G. Pino