In the Live Support are different information are available (i.e. Suggested Solution, Recent Incidents, Offering, etc)
Information to actual active changes (primary offline changes) for this service or CI should be available too.
In case of user call the Service Desk can determine/related the issue call to the actual change. In the most cases the information to user "your service is planned stopped by change," is sufficient and no further activity is required.
This reduce useless support effort.