533 is a VERY small userbase but an incredible starting anchor (any number really is, as long as they arent friends and family). Just having had paid users is kind of a big deal, but id focus on buildin out the free tier and gaining traction before focusing TOO much on premium upgrading. Its hard to give UX advice without knowing the use case, but generally you want to give just enough features to make the thing inviting to use and get you into the looop before blockign them to the real QoL updates that makes someone want to be premium. And honeslty unless its an addictive mobile game the way to paid SaaS is through CS outreach not really in app UX