I just did. Got the email at 11:04, clicked on the link at 11:05. All it did was take me to the login page (it happened for our outbound flight but I didn’t see th email for a couple of hours so accepted that the offer was long gone). When I called the Platinum Pro line the rep transferred me to the tech department, which insisted that all of the offers come via email, but that if the offer is still valid, it will show up in the app.