You are always free to upgrade your device when ever you choose to. However, you still need to complete the term left on your current device. You can continue to pay that monthly and purchase another phone for the full cost and move your SIM to the new device without any issues. If you want to use your current device you are paying for as a trade-in, it needs to be fully paid off first unless it is a finance. You might have to look at the terms of the finance to see if there are any early termination feed.
There are places, like Visions Electronics, Canada Computers, and others that sell devices where you can pay them off monthly through their Flexiti financing. This would not impact your current payment contract with Rogers and you would simply move your current SIM from the device you are using to the new device.
