That's correct! I imagine you could run the tool a few times after a system restart or two if not immediately trying to upgrade in order to grab the other edition Home or Pro, not Home N or Pro N for home use in the US for sure in case you have another system that will need or run the other of the two choices. What that means if you are 7 Home Premium, 8, or 8.1 you wouldn't be stopped from downloading the Pro or Pro N edition.
BUT! And this is the important thing to remember the type of questions you are asking here are already covered on the FAQ page regarding things like the difference between the 32 and 64bit Windows as well is the media bootable seen at FAQ as well as finding answers on Q&A page for things like the Upgrade Chart that shows which edition you pick depending which edition you have on a system for a previous version you are trying to upgrade. Windows 10 FAQ Tips - Microsoft
Question & Immediate Answer:
What edition of Windows will I get as part of this free upgrade?
When you upgrade, you’ll stay on like-to-like editions of Windows. For example, Windows 7 Home Premium will upgrade to Windows 10 Home.
From Edition To Edition Windows 7 Starter Windows 10 Home Windows 7 Home Basic Windows 7 Home Premium Windows 7 Professional Windows 10 Pro Windows 7 Ultimate
From Edition To Edition Windows Phone 8.15 Windows 10 Mobile Windows 8.16 Windows 10 Home Windows 8.1 Pro Windows 10 Pro Windows 8.1 Pro for Students
“N” and “KN” editions follow the upgrade path of the parent edition (e.g., Windows 7 Pro N upgrades to Windows 10 Pro N).
Some editions are excluded: Windows 7 Enterprise, Windows 8/8.1 Enterprise, and Windows RT/RT 8.1. Active Software Assurance customers in volume licensing have the benefit to upgrade to Windows 10 enterprise offerings outside of this offer.
That explains for 7 Starter, Home Basic, and Home Premium editions you can only upgrade free of charge as long as the 7 installation is geniune to the correct edition of 10 being 10 Home! Same goes for 8 Home seeing 10 Home as well as for 8.,1 Home. The combination disk with then simply see the option to upgrade to either the 32bit or 64bit 10 Home while booted in the previous version or boot live and then choose which flavor!
The same applies for the 10 Pro edition upgraded over 7 Pro or Ultimate, 8 Pro, or 8.1 Pro. Once you select the one edition then you choose which kernel or both 32/64 for the download to begin for either immediate upgrade or installing 10 at a later time. If you go for the Home edition due to having 7 HP for example on the first machine and have another 7 Pro or Ultimate system you want to upgrade but might not have internet connection or for an 8.1 mobile device like Windows Phone for example you then would run the tool again in order to save the iso for the other edition if not making up the media on the spot.
Actually I used a utility I downloaded for seeing 7 put on flash drives back in 2009 I used again for seeing 10 media made up! The tool besides being a media creation tool being provided by MS for those without any such program is also the method MS put inplace other then direct by Windows Updates to see 10 downloaded. You can still use another dvd burning program as well as some other USB tool to get the task seen to.