The time of day economizer control schedule only activates actives economizer mode according to the schedule. It does not disable economizer operation according to other inputs.

if ( EconomizerAirFlowScheduleValue > 0.0 ) {
    EconomizerOperationFlag = true;
    OutAirSignal = 1.0;
}

So the economizer should be on anytime the schedule values are > 0. If you set other inputs to not allow economizer operation (e.g., leave other limit input fields blank, for example Economizer Maximum Limit Dry-Bulb Temperature) then the schedule should work as you expect.