I suspect my issue is related to entering @icloud for my Apple ID, when I’m actually signed in @Mac. Despite entering @Mac over 48 hrs ago with the ‘notify me’ link, I’m not able to apply.
Not sure this is the issue... I use @gmail.com for App Store and my main email... and an @me.com as my AppleID for devices... I entered the @gmail.com address... I got the email earlier in the week asking me to re-submit the request using my AppleID (@me.com). In a bit over 24 hours, I had my Apple Card invite, submitted the app and was approved.