Yes, this can be done using an Advanced filter. Please see the below example advanced filters.
At least 1 active subscription:
Code:
( ( SELECT COUNT(*) FROM `#__cbsubs_subscriptions` AS sub WHERE sub.`user_id` = u.`id` AND sub.`status` = 'A' ) >= 1 )
Active subscription of a specific plan:
Code:
( ( SELECT COUNT(*) FROM `#__cbsubs_subscriptions` AS sub WHERE sub.`user_id` = u.`id` AND sub.`plan_id` = PLAN_ID_HERE AND sub.`status` = 'A' ) >= 1 )