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Calendar hours are regular full-day round-the-clock hours. If you promise your customers 24/7 support, you need to use calendar hours as the basis of your SLA policies.
Operating Hours refer to the working hours of your service team. When chosen, the SLA clock for your tickets will not run outside of working hours. You can specify working hours for each day under Ticketing & Messaging > Settings > Working Time & Holidays.
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（6）Set Conditions for when the Service Level Target created in step #5 applies.
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