If you go to App Store and download TestFlight App, then go here, you can install the latest version if it’s available. I understood vrod (npub1h50…rqev) to say some may be available. 🤙🏻
If this link doesn’t work, search for Damus TestFlight on your phone web browser.
https://duckduckgo.com/?q=damus%20testflight+site:testflight.apple.com