After selecting "Downgrade to Free" from the bottom of the Pricing page and following all of the steps, it begins a process to cancel your subscription at the end of the current billing term.
Since you have already paid for your membership, you won't downgrade to free until the payment period has ended. Until that time, you will have unlimited access to our library of assets and products.
You can confirm this on your "Manage Subscription" page. Once you select the free plan, the message in the screenshot below will appear, notifying you of when your account will be set to free: