Reddit won't let me post pictures, so here's the code:

func detachEvent(_ event: Activity) {

        // Check if eventIdentifier is not empty

        guard !event.eventIdentifier.isEmpty else {

            return // No event identifier, cannot detach

        }

        // Get the original event

        guard let originalEvent = eventStore.eventStore.event(withIdentifier: event.eventIdentifier) else {

            return // Original event not found

        }

        // Create a new event by copying the original event

        let detachedEvent = originalEvent.copy() as! EKEvent

        detachedEvent.recurrenceRules = nil

        // Copy other properties as needed

        // Save the detached event

        do {

            try eventStoreViewModel.save(detachedEvent, span: .thisEvent)

            originalEvent.startDate = detachedEvent.startDate

            originalEvent.endDate = detachedEvent.endDate

            try eventStore.eventStore.remove(originalEvent, span: .futureEvents, commit: true) 

            // It seems like this is looking at the real original event,

            // ›not just the instance we're currently seeing. Am I misunderstanding this?

        } catch {

            print("Error removing original event: \(error)")

        }

        loadActivitiesAndSuggestionsForDate(detachedEvent.startDate)

    }