When an employee is called back for overtime after they have left the employer's premises, whether told before or after leaving, they must be paid for at least 3 hours (plumbing and mechanical services employees) or 4 hours (sprinkler fitters). Unless something unforeseen arises, they need not work the full minimum if the recall job is finished sooner. The clause does not apply where it is customary to return to the premises for a specific out-of-hours job, where the overtime runs on (apart from a reasonable meal break) from the start or end of ordinary time, or to service work.
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