Where are you getting that number? The pod shows insulin remaining in amounts from 50 units down to 5 units. Once it gets below 5 units, it says “Low”.
So the PDM would never display 0.5 units remaining.
Do you mean 5 units?
If you are ever in a jam for the pod running out before the expiration, just let the pod do basal, and bolus with a syringe. And that will make it last longer.