Missing the visual upgrade option on SP 2010 site

I have a series of content databases that were upgraded from MOSS 2007. Most have not yet undergone the visual upgrade.

Today, I have been working on copying two of those sites to a new location.

I created two new team sites. These of course already had the visual upgrade.

I did an export-spweb of the two old sites. I then did an import-spweb of the two old sites into the new sites that I created.

The result is the two old style GUI in the new location.

When I took a look at the site settings (as a farm admin) I do not see an option to perform the visual upgrade on the sites.

I know that there are powershell commands that I can execute when the time is right.

I don't understand, however, where the visual upgrade option went.

Hmm - I just went back to the original sites that were copied and they too do not have the visual upgrade option in the site settings.

The top level site does, however, have that option.

Odd...