Find your customer tags. Navigate to Customer Experience > Tagging

If you only have one selling plan you can copy the tag

If you have multiple selling plans, you will want to Add Dynamic Variables to assign the right customer tag to the right selling plan. 

To find the selling plan ID, navigate to a product page on your store, select the selling plan and this will update the URL.

You can then substitute this in and type '688127050017appstle_subscription_active_customer' into Sky Pilot