Yes. The serial number you purchase is good for all platforms, and it doesn’t matter to us how you allocate it. So if you purchased multiple licenses, you could install on any combination of Mac, Windows or Linux machines. (Of course, only DF4+ supports Linux.)
You can also deactivate your license on one platform and activate it on another. (Deactivate License… is an option in the Help menu.)
Then download the latest version for your license on our Downloads page.