That clause has been in every PUP email since the beginning of the program, yet they have never awarded PUP in anything other than multiples of 10.
We never got this last year, and I'm not expecting it this year. We do both get the regular PUP emails.
The app isn't accurate even when you're on the cruise. Trust it to your own peril! On our last cruise, I ordered based on the app three times and every time was told "that's not on the menu".