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DesignSpecification:OutdoorAir (DSOA) is primarily used for sizing (which ignores the schedule), but it can also be used for control in certain situations:

• Controller:MechanicalVentilation references a DSOA for each zone on the system. This is the only way to control the central OA amount based on the schedule in DSOA.
• Several air terminal units (`AirTerminal:SingleDuct:VAV:NoReheat, AirTerminal:SingleDuct:VAV:Reheat, AirTerminal:DualDuct:VAV may reference a DSOA object. For VAV terminals, this control will first set the airflow rate based on the thermostat requirement (and the specified minimum flow rate). Then the supply air OA fraction is applied to the supply flow rate to determine the amount of OA the zone will received. If the current DSOA request (including the DSOA schedule) is greater, then the VAV terminal unit will increase the supply airflow in an attempt to meet the OA requirement. Other than changing supply flow rates, there is no feedback to the central system OA controller.
• ZoneHVAC:IdealLoadsAirSystem and ZoneHVAC:HybridUnitaryHVAC use a DSOA reference to control OA flow for these single-zone systems.
• AirTerminal:SingleDuct:ConstantVolume:NoReheat, AirTerminal:SingleDuct:Mixer, AirTerminal:DualDuct:VAV:OutdoorAir use a DSOA reference to set a flow request from the central air system.

For the example files 5ZoneFanCoilDOASCool_rev and 5ZoneWarmest_Rev, add a Controller:MechanicalVentilation object to control the central OA based on the schedule in the DSOA object.

For the example file VariableRefrigerantFlow_5Zone_rev, the OA flow rate for ZoneHVAC:TerminalUnit:VariableRefrigerantFlow cannot be scheduled. It will be one of three fixed amounts as specified in the "Cooling/Heating/No Load Outdoor Air Flow Rate" fields.

So, this is working as designed, even if it is a bit confusing. As general rule, DesignSpecification:OutdoorAir is only used by the objects which reference it directly.