I think the people in a squeeze are owning the newer developments, basically sold in the past 8-9 years. For a few reasons:
1. They could through the developer borrow up to around 85%, so they are highly leveraged
2. The new properties are sold at a premium price, as the building now is 5+ years old, the resell value starts to decline, as its no longer new. So not only is property market falling, their flat is falling faster than the market.
3. People jumping on these deals are usually younger, meaning their financial stability is not as high as for people close to retirement. Its been tough times for some job wise these past years, there are probably people unemployed or who had to take significant salary cuts holding these flats.