You get the upgrade price because PGMusic should have a record of your previous purchase(s) to verify that you qualify for the upgrade pricing. If you bought it from a retail store, I suspect you will have to provide proof of purchase to get the upgrade price. You would have to discuss that with PGMusic.

Assuming they haven't changed it this year, for installation, the hard drive you receive is a complete package (but possibly minus any special add-ons that may have been received over the years), and it doesn't have to "see" the previous version installed on your computer to use it. It's like buying the 2018 version as a first time customer, but with an upgrade price (hope that made sense). You will also receive a new authentication code to use.

You do have several installation options. If you use your 2016 version from the USB drive and don't plan on going back to 2016, you could install 2018 on top of your 2016 drive, then use 2018 as your backup. I'm pretty sure if you have 30GB left, there should be plenty of space for the new content from 2017 and 2018 (which you currently don't have).

If you run it from your computer's hard drive, similarly, you can just install over your 2016 installation and then keep the 2018 USB as a backup.

John

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