The thing is call Google Dancing..
Read these articles >> [1] http://www.metamend.com/google-dance.html
[2] http://www.searchguild.com/article3.html

The name "Google Dance" is often used to describe the period when a major index update of the Google search engine is being implemented.

I know what google dance is, what I am talking about is nor google dance unless google dance is now weekly

Temi, this is a weird thing that Google has. I regularly bounce in and out of page 1 to like page 20 for the phrase 'internet marketing company'. There is no rhyme nor reason for it, other than a temporary loss of a powerful backlink(s) . If a site is down then you will bounce out. Then again if a page is up you might bounce in.

It is a right PITA, but the good news is that eventually you will settle into the position where you sometimes see yourself.

OWG,
Your response describes the EXACT problem I am having because you normally expect to drop to page 2 or page 3 form page 1 and not page 20 only to reappear on page one in a few days time, I am pleased its not happening to me alone as I was worried it was something I was doing wrong, thanks very much for sharing your experience, it give me confidence that its Google thing rather than me.

I would advise you to check on a particular datacentre as this is the only way to get consistent results. Or you could run a check on lots of data centres, do you do this? if so what tool do you use? I can give you an address via Pm that will allow you to check quite a few data centres simultaneously.

I don't check the data centres, I just use the standard Google search which I supposed could return results from any data centre so I don't use any advanced tool, PM of a tool to use would be greatly appreciated.