If you are looking to add a single new channel or carrier integration, and your current plan doesn't allow it, you will need to upgrade first to the next available plan. 

If you are running tests on a potential new courier or channel, you can downgrade back to your original plan once you are done with your tests. This applies to those who are changing from one channel/carrier to another.

For more information on how to upgrade/downgrade your subscription, please visit the below guide:

How Do I Upgrade or Downgrade my Subscription?

If you have questions or need anything else, please feel free to contact support.