Once your ad spend changes you might want to change your current plan, the system does not adjust it automatically.
You can upgrade your account any time following the steps below:
Open the Upgrade page
Click "Show all Revealbot plans" if you don't see the plan you need
Pick the plan that suits you best and upgrade
Likewise you can downgrade your subscription to a lower plan.
Make sure to read this article before you upgrade to learn how you're billed in cases where you change the plan during the billing cycle.