Use this Drip™ Workflow for Subscription Managment and continuosly profile Subscribers. Then, use Segmentation and engage with them in a meaningful way!
This Workflow triggers when first_name custom field is updated. Then, a decision step checks if the subscriber was ever profiled or not by checking if either of the two custom fields, last_profiled_date or not_profiled_date, is set. If yes, go to the next decision. If no, proceed with subscription management emails.
This decision step is to check if last_profied_date or not_profiled_date is within the last 6 months. If yes, exit the Workflow. If no, proceed with subscription management emails
After sending emails for a subscriber to submit their preferences, if no submission, record and event, set the custom field, not_profiled_date, and exit the Workflow.
If the subscriber submits the Form, then the Goal is met, tags are applied, event is recorded, custom field last_profied_date is updated, and then exit the workflow.
Two separate Rules are needed to restart the Workflow after 6 months (if profiled) & 3 months (if not profiled) based on the trigger of the two custom fields, last_profiled_date and not_profiled_date respectively being updated by the Workflow initially.
NOTE: You also need a Subscription Management Form, obviuosly 😉