I stayed at the Sydney Westin last month. I had booked the first night on the web, and the following nights using a Diamond Club coupon. Both reservations were on the club floor. On arrival, I was told that the two reservations could not be married because we had booked a higher category of room for the first night than the subsequent ones. (Note: utterly nothing in our reservations indicated a difference in club floor rooms.) I was told we would have to move after the first night. I asked if we could be left in the better room, since we are Gold and that entitled us to an upgrade. I was told that the property only upgrades Diamond; that Gold are not entitled to upgrades.
In the end, the Concierge on the floor was marvelous and worked it all out for us - but not because we were gold, but because he was a decent guy.