It's not just a license. It's a package that is included in one distribution of the firmware. So there is a version of each firmware with it and without it. Since you can't downgrade you'd need to find a way to reinstall the same version of the firmware you already have installed with the package. That seems unlikely any time soon. Just format your card FAT 32 if you want to use it. Although if you aren't upgrading firmware I'm not sure what you need the sd card for.