Setting QoS on the IotMqttPublish function block (IotMqtt_QoS1 vs IotMqtt_QoS0)

[MaximBozek-M-ECS]

PublishClient(
      Enable := TRUE,
      IotMqttLink := MQTTClient.IotMqttLink,
      Topic := ADR(topic),
      QoS := IotMqtt_QoS1,
      Buffer := Buffer,
      BufferLength := Buffer_len,
      Retained := FALSE
);

Putting this QoS parameter to IotMqtt_QoS1, what does this actually do in the backend? if this is turned on, does the server send back a response which gets handled in the backend, to which the "Done" boolean is switched? I don't notice any difference when putting it to IotMqtt_QoS0.

Is the "Done" boolean switched based off of this QoS parameter, or should I look at "Info.DeliveriesCompleted"?

I am currently also subscribing on a self-fabricated response from the server, but if this works, I can scrap that part of my code.