If "Cancellation and Rescheduling" is allowed, the cancel and reschedule links are included in the confirmed booking email upon successful booking. The client can reschedule the existing booking by choosing a new date and time.
If the client does not see the option to cancel or reschedule a booking in the email, the meeting host does not allow cancellation or rescheduling. In such cases, the client must contact the host to cancel or reschedule a meeting.
Meeting changed directly in the calendar will causes mismatch with NeetoCal
If a meeting is rescheduled directly in Google/Outlook/iCloud calendar and not using NeetoCal, then NeetoCal will NOT be aware of the change in the meeting schedule. This will cause a mismatch between Google/Outlook/iCloud calendar and NeetoCal. So, it's best to reschedule the meeting using NeetoCal only.
The meeting canceled in the calendar will be canceled in NeetoCal too
If a meeting is declined or deleted in the Google/Outlook calendar, NeetoCal will also mark that meeting as canceled. The cancellation reason will show that the Host (or client) declined/deleted the invitation from Google/Outlook Calendar.
If someone is using iCloud Calendar and declines the invitation or deletes the meeting, the meeting will NOT sync with NeetoCal. In this case, NeetoCal will continue assuming the meeting is still scheduled.