Hi @Mike J. … the Apple App Store can funky about ‘publishing’ new versions. Updates will appear eventually, tho’ if you want to grab the latest version on your iPad right away:

• Open the App Store
• Search for Sonos and select the Sonos S2 app
• When you open the page for the app (with the description) you’ll get a proper ‘Update’ button

This advice worked perfectly!  Thank you.