Previous deal is well over 12 months old, and I think we are overdue for a reminder. Furthermore, a few things have changed since 2017, so this may not even be classified as a dupe in the first place.
What's new?
Firstly, this license lasts in perpetuity,
With more features than ever, like Windows Ink, Paint 3D, and mixed reality, Windows 10 Education is Microsoft’s most robust version yet — and it’s yours, even after you graduate.
and unlike Office 365 which will only last for four years, this will be linked to your Microsoft Account forever. To my understanding, this may also be transferrable as it is linked to your Microsoft Account (and it is definitely not an OEM license / fixed to hardware).
Microsoft also advertises that Windows 10 Education has more features than even Windows 10 Pro. Cortana is now included where it was not before. I believe it is still mass licensed, similar to an enterprise agreement, and thus, it has some enterprise features that Windows 10 Pro does not have.
Where Office 365 is available to any student (or teacher) with a .edu email address, similar offers for free Windows 10 seemed to be limited to whichever schools (or in my university's case, sub-faculties) were willing to pay for an enterprise license.
Now it seems that Windows 10 Education is much more accessible, and is no longer limited by such enterprise licenses, and may even be as widely available as Office 365.
Hope this helps people, as many people seem to be building PCs right now! This is exactly how I found about this, having trouble transferring my digital license, and then discovering I could just obtain a free license code for being a student. I'd be curious to know if any students have eligibility issues now, so let me know in the comments. I know previously, my university offered free Office, but not Windows unless you were in specific faculties like computer science, or engineering.
I bought a dodgy Win10 Pro key (~$5) off eBay with the aim of claiming a refund if it didn't work. However, it worked fine.
Surprisingly, when I had to reinstall Win10, it automatically activated itself the moment I signed in with my MS account. So I am guessing once you get hold of a key and use it under your MS account, Windows is activated forever under that account. No more keys needed.