Windows Anytime Upgrade

Can't seem to find the answer to this anywhere, so thought I'd ask here.

When Vista first came out I downloaded a 32-bit version of Vista Business from my uni's MSDNAA site. I wanted to be able to use media center, so I bought a Windows Anytime Upgrade license to upgrade this to Vista Ultimate.

I've since got a new computer with a 64-bit processor and I'm considering the move to 64-bit Vista. I can get a 64-bit version of Vista Business from MSDNAA, but I want to know whether my Anytime Upgrade license will work to upgrade this to 64-bit Ultimate?

Anybody got any ideas?

Cheers

I'm almost sure it will work. Just search for 'windows anytime upgrade' in the start menu and click the icon to start. :)