Is The Sub-500K Market In Trouble?

Despite the troubles that are hitting the property industry, the banks have been adamant that because of high demand the low-end of the market (houses priced below R500 000) is still pretty buoyant. But have a look at this quote from Realestateweb:

John Loos, property strategist with FNB Home Loans, notes that the "lower end" of the market where properties cost about R500 000 is "still stronger" than higher up the property price scale, but this "could be changing".

'could be changing'? Now I don't work for a bank nor am I employed as a property strategist, but what new information or data does John Loos know about the sub-500k market that makes him say the strength in that market could be changing?