Weird one... So I had a recent Hilton stay, booked using the "old" Points & Money. It appears that I have earned 15 points per $ for the cash portion. However, my account is set to Points & Miles but there's no corresponding mileage being earned. Have I missed some change in the T&C's? But why no miles then?
I believe they did change P+M stays to earn points on the cash part, as part of the recent HHHHHonors -> Honors changes. As per http://loyaltylobby.com/2017/01/31/...nts-pooling-diamond-onetime-status-extension/ (can't find the magic text on hilton.com!) it should be Members will earn points and airline miles based on the paid portion of the rate. Like you, for a pre-change P+M booked stay, I got points but not miles. I wonder if that's just an artifact of the changeover?
I also read somewhere recently, but then lost the link, that incidental spend never earned miles, just points?