You're right. Thank you for pointing this out
I just made the update on my iPhone and wanted to try this new feature for a check-in in a Sofitel today, but I didn't see anywhere this check-in option.

Also, slightly OT but about the app :
- Why is it impossible to see the history of points earned ? This is a very basic information members want
- am I the only one to have this very annoying problem when logging-in on the app : when typing my login, I'm redirected systematically to Safari and the mobile site of Accor. So I go back to the app and sometimes it's OK or again redirected to the mobile site after having typed a few more characters