In patients using a tandem insulin pump on auto-mode/Control-IQ, would decreasing the basal settings on the profile actually reduce the delivered hourly insulin dose or is that only relevant if they switch to manual mode?  

The Tandem Control IQ differs from other pump brands in that the preset basal rate is still used even in closed loop mode; however, the pump will adjust the basal rate up or down if high or low glucose levels are predicted. In other models, the preset basal rate is not used at all in closed loop mod...