com.snc.sla.calculation.always_run_relative_duration_script

ServiceNow property description:

Set this property to "true" if the relative duration script should always be used to calculate the duration of a Task SLA that is based on a relative duration. With this property set to "false", the relative duration script will only be executed once when the SLA is attached and subsequent calculations will use the "Original Breach Time" field to derive the duration of the SLA.