I understand that PM is a prepaid service and it does not refund any money already paid. That being said, many times, a user may want to change his/her existing plan during the mid course of the service term. PM allows those changes and charges the user the full costs of the new plan chosen. However, there is NO warning message that once submitted the change, the user will not be getting a refund of the money for the remaining term of the current plan.
I am suggesting PM to provide a warning message to ensure the user is aware that there will not be any refund for the remainder of the current plan to be replaced. This should be a very simple fix for PM.