How Does Server Determine Age of Uploaded Images?

I found some older images that I need to run through VPhot.  When I tried to upload them, they did not show up. The date in the FITS header is older than 4 months, and I know that VPhot does not keep images older than 4 months old. So does that also mean one cannot upload images older than 4 months old?

Thanks for your help.

Michael