I bought the iPhone 5s in December with the plan being the: $39/month CAN Data 400MB 400min. I paid $300 and as of today I have a -$172 tab balance, so I was wondering if I could upgrade to the new iPhone 6? If so, do I need to pay off my tab entirely? Also, will I be able to keep the 5s or will I have return it to Koodo when upgrading? The reason I ask is because I want to give the IPhone 6 to a family member. Thanks for all of your input!