rebadc

I have a few assumptions that I would like some help with.
One, elite benefits apply to award redemptions
Two, upgrades subject to availability means that if the upgraded room is available for cash, its available as an upgrade for elite members
Three, there is not a limit on days an upgrade can be given

I am a LTT Elite and have just checked into a residence for 9 nights on a mix of points and Chase free night certificates
The property only has two types of rooms Queen Suites and "Duplex Penthouses"

I had Bonvoy chatted with the hotel prior to arriving asking for an upgrade to the Duplex Penthouse
They came back to me and said the Duplex Penthouse is not available for the duration of our stay.
Not true, I had checked prior to chatting and the duplex suite was and still is available while I'm posting

I check in and ask again, no upgrade, the operational manager came out and seemed to indicate that if we were staying for a few nights the upgrade would be given but for our extended stay they could not.

So I'm going to the experts here with my assumptions that if an upgraded room is available for cash its available for an elite upgrade, that it does not matter that the stay is on points, and that the duration of the stay does not matter.
I further assume that management wants to hold the Duplex Penthouses for cash travelers , which I totally get

I am often wrong in my assumptions, what does the collective think?
Thanks.