I have yet to EVER get a text, even when I arrived early (before online check-in) and the CM at the desk personally typed in my phone number.
It doesn't always happen - and they have never guaranteed that online check-in will get you the text or ability to skip checking in in person.
Worst-case, quick sponge-off (and maybe change) in the bathroom, store your luggage with bell services and go to dinner, then check-in when you're finished with dinner.