The function of the Subscription Frequency Selector is to filter the plans in the Pricing Selector. 

The Subscription Frequency Selector can be easily activated or deactivated.

When activated, the selector will appear at the top of the payment form. 

The filter applies to all the frequencies available based on all plans created.

When deactivated, the plans in the Pricing Selector are not filtered by subscription frequency. All plans will display simultaneously unless they are being filtered by the Currency Selector.