For active customers I am tagging people when they take certain actions with the Shopify Flow app, then I have have flows set up for those tags.

But is it possible to tag existing customer profiles in Klaviyo where they aren’t necessarily taking action on the shopify website.  For instance we have some older lists which were imported from mailchimp, which don’t really need to be lists (3 lists - ex members from years 1, 2, 3 of a membership), I want to delete the lists, to tidy up our lists and segments, but I’d like to tag the customers in those lists with a tag so that if we want to create a segment to send an email to all the ex members of a membership in the future, we could. Is that possible?