This should be configured in Load file as “duration” entity.

  <Input_Reference>
    <datetime>2022-05-24T22:10:59+05:30</datetime>
    <id>2022_5_24_22_10_59</id>
    <input_type>LOAD</input_type>
    <organisation_id>1</organisation_id>
    <dataset_id>TEST</dataset_id>
    <schedule_data>CONTINUOUS</schedule_data>
    <load_status>-1</load_status>
    <duration>P14D</duration>
    <appointment_window_duration>PT21D</appointment_window_duration>
    <process_type>DYNAMIC</process_type>
    <enacting_app_type_id>SIM</enacting_app_type_id>
  </Input_Reference>

If you are using FSM PSO integration, you can set INPUT_REF_DURATION Scheduling App Parameter. Then this will reflect in next Load file sending to PSO from FSM.

Worth noting that it is recommended to keep the scheduling window to minimum number of days. 

Hi,

I don’t think that will solve my actual problem, I think the INPUT_REF_DURATION only moves the “dotted blue line” in PSO, instead of the blue line which is shown like this in the legend:

Yes, blue dotted line indicates the end of Scheduling window or start of appointment window. INPUT_REF_DURATION will adjust this.

If you want to adjust blue solid line when Appointment booking is using, you can alter appointment_window_duration. Relevant FSM parameter is APPOINTMENT_WINDOW_MAX_DURATION. 
Note that, these 2 are not overlapping. Eg: In my above example, scheduling window is 14 days and appointment window is 21 days. That means in Gannt view, you will have 35 days.