How do business hours work with SLA targets?

A business schedule is a named weekly calendar: for each weekday you set whether you are open and between which hours, and each schedule has its own time zone. An SLA target counted against a schedule only ticks while you are open, so nothing breaches overnight or over a weekend. For example, a ticket that arrives Monday 16:30 with a one-hour first-reply target on a Mon–Fri 08:00–17:00 schedule is due Tuesday 08:30, not Monday 17:30. A rule with no schedule counts plain calendar hours around the clock. Public holidays are not yet part of schedules.