Amusing 'POA' feature in PH classifieds

[samoht]

If you load this search for 996 GT3s, the red car will show with price 'POA'.

http://www.pistonheads.com/classifieds?Category=us...

However, if you then flip the filter at the top to change the sort order, lo and behold, the price is shown as £45,996. Refresh the page with F5 and the price disappears again.

Is this deliberate? Kinda amusing tbh.