Is my provider re-routing my online activity?

Hi,

I trust this may be the correct forum for my question:-

I recently changed my password for ebay and received an acknowledment to check that it was indeed me that changed the password.

My IPv4 address is 192.168.x.xx.

The email from ebay said that the password had been changed from IP address 86.5.182.75!

I clicked onto a site that I knew from previous experience showed the IP adress that was visiting (to show how easy itis to identify an I.P. address). It too showed my IP address as 86.5.182.75.

I telephoned my provider (Virgin) technical support to ask why this was happening. The advisor had to consult a supervisor. The reply I then received was that my IP address is only valid as far as the router. From the router to any visited site, it was then Virgin Media's IP address that is displayed.

I find that hard to believe.

Can anyone confirm that this information is correct - or conversely that it should not be please.

Thank you for your time and consideration.