Last month I changed my plan to the $29 Canada wide plan. I got my first bill since changing my plan and it says that my monthly service charges are $36. That'a before the $5 unlimited texting add on, taxes, and the minutes I went over. Where did the $7 dollars come from?
It's proration on the changed plan. Take another look at your bill and you'll see that you have a credit on the old plan and debit for the new plan, the difference is proration. That's because you're billed one month in advance so you got a credit for the days you're not on the old plan because you changed it, and debit for the new plan from the date you changed it up to your invoice date. All providers do this.