Hi,

https://docs.servicenow.com/bundle/london-it-service-management/page/product/service-level-management/task/t_CreateAnSLADefinition.html

This has information what you are looking for. This enables to define SLA to follow the schedule based on fields defined on TASK.

eg, you can create a schedule field on sys_user_group table and have it used in SLA definition so that when incident gets assigned to particular group, it will follow the schedule of that group. Likewise, you can leverage schedule fields from CMDB , business services etc.

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