HHDiamond status match challenge - 8 Stays within 90 days.

Is a Day Use stay a valid "stay" that contributes towards your 8 nights for a status match challenge.
A Day Use booking registers as 1 stay and 1 night on the system.
It is valid for promotions such as double/triple points, Miles and More air miles promotion currently on.
However I've been advised that it wouldn't count towards my challenge.

If a Day Use doesn't count then I wouldn't want to book another Day Use rate as I'll need to 3 more bookings to complete the challenge.
I have 7 stays currently complete for the challenge, 2 of which are Day Use since I was flying in the evening and didn't need the night rate.
Has anyone had history with this? Any advice/comments?

Thanks