When subscribing to Pro or Business plans, you have two options - monthly or yearly payments. Both are automatic, recurring payments, and you can cancel them anytime by going to your account settings.
We recommend cancelling your subscription at least a couple of days before the next scheduled payment. You'll be able to access the plan's features until the end of the subscription period (therefore, if you need the advanced features only for a couple of months, we suggest choosing the monthly subscription). Make sure you download your invoices before you unsubscribe (they are also located in your account settings) as after the end of the subscription period you won't have access to them.