http://hl7.org/fhir/StructureDefinition/procedure-schedule|5.2.0

The schedule that was followed. Use Procedure.occurrenceTiming in R5+

element_id	types
Extension
Extension.extension
Extension.url
Extension.value[x]	Timing
Extension
Extension.id	http://hl7.org/fhirpath/System.String
Extension.extension	Extension
Extension.url	http://hl7.org/fhirpath/System.String
Extension.value[x]	Timing