JimmyT, Scotllandx thank you for your replies. The owner did get a DA from council showing there was a media room and 2 bedrooms. This and a large contribution to the sinking fund was the basis for the OC agreeing to stamp the application.
The block is 5 levels. There were 3 levels with 2 units per floor, a garage and the basement. The basement is smaller than the levels above due to the block being built next to and above a rocky embankment. Our understanding is that the original builder intended to have a unit built on this level but would have required a lift to be installed or an additional parking space allocated to meet building code at the time. I haven’t confirmed either story yet.
As for unit entitlements, the original allocation of 215 unit entitlements gave this lot owner 65 units and the 5 other lot owners 30 units each. This hasn’t changed though I think the new lot will have 35 unit entitlements and the original apartment will have 30 unit entitlements. This was raised at the time and an opinion was to be obtained but I don’t recall the outcome. Can anything be done about the lot entitlements now?