I have made further checks, and found another site
www.sapphirewatersmotorinn.com.au has also been dumped. Only the main page appears to have been dumped on any of these sites as some still have subpages listing. I mention this site as it has no layer text and therefore is not in the same catagory as those mentioned previously.
I use a programme "WebPro Gold2" to promote my sites, the authors have recently released a newsletter which denies that 'using their programme might cause you to be dumped'. I have also promoted them manually from time to time - especially my current promotion, from which I patiently await the results of the next Google dance.
Seems there is no consistancy in this Dumping.