I setup my agency on Tern! I need to convert my personal account to a seat under the agency. I see where I can do that and then cancel my personal subscription. Will it charge me again when i buy the seat? If so, is the other subscription refunded?

In most cases you should set your personal subscription to stop auto-renewing, add yourself to the agency as a "Free Seat", and then convert to a paid agency seat once your current subscription is complete. That way you avoid double paying for Tern.

Tern is not able to offer refunds in the event that you pay for two subscriptions at once.

When you add users to your agency you can decide what type of seat they should have. This is true for your account as well. A "free seat" just means the individual is responsible for the billing. By setting your account to a free seat you will get all the benefits of an agency without double paying.

You can edit the agency seat type at any time under the settings. More details can be found here.