Archived and Closed
Since the old tabs include a 15% contribution from koodo toward your tab balance up to $150 positive balance, and the no-tab discount of 10% were in place to account for the old plan/phone prices/markups, it makes more sense (assuming you're happy with your current device/plan) to keep your existing plan and tab. This is because you're getting 15% per month for free from koodo towards an upgrade (your existing tab). The current phone prices aren't marked up as much to account for the new plans and new tab (no more koodo contribution, no 10% plan discount), so when it comes time to upgrade, you're getting more of a discount on your phone.
When you're ready to upgrade, the new plans are still going to be cheaper than the old ones, the new phone prices will be cheaper than the old ones, and now you've been getting the same 15% contribution from koodo towards them (or 10% discount on your existing plan) until you're ready to upgrade.
I did the math on my specific plan, and it's actually going to cost me a lot more (based on my current plan, and usage) to change to a new similar plan, and tab. For me, it makes sense to wait until i have $150 towards a new phone.