A useful support SLA states the target (for example, a first response within one hour), the hours it applies to and their time zone, the channels it covers, and how priority changes the target. Many teams set different SLAs per plan or account tier.
An SLA is external; an internal target is usually tighter so the team has headroom. Measure attainment as the share of requests that met the target. In Weft, SLAs and escalations are part of the Growth plan.