In this case shouldn't those extra minutes be rolled over to the next plan instead? I was charged over $30 extra for this reason, yet the (reduced) minuted were still calculated based on a full billing cycle (i.e. I was given 168 for a full month, despite having 200 minutes/month for each plan).
I can understand if you were joining, however I have been with Koodo around 5+ years and never had this happen before (I always check any overages). What I don't understand is that I was being charged for a full month's rates (I was charged my usual monthly rates for the plan despite changing around 2/3 of the way in), being billed for a full month period (the period the calls occurred was over a full month cycle), yet only being provided a portion of the services I am paying for.
Calls are billed to the plan you are on at the time. If you change your plan 2/3 of the way through the month, you will be refunded 1/3 of the price of the old plan, while being alloted 2/3 of its minutes for that portion of the month. You will be charged 1/3 of the new plans price for the rest of the month, while being alloted 1/3 of the minutes it includes.