There's no difference yet. These are new placeholders for when things start forking next month with the 16.16.1/16.17 releases (that's why everything has the same URL/hash for now...)
Next month, Office 2019 will be officially released and that's going to be the Office 365 installer which is version 16.17. Office 2016 will still get security updates and it's version will be increment from 16.16.x to 16.16.y to 16.16.z and so on.
That's also why you see the Minimum OS column. Office 2019 will support 10.12 until January 2019 at which point it will support 10.13+. And this will be a yearly thing where Office 365 will support N-1 operating systems.
@bpavlov and @maser Thanks for clearing up. So yesterday patches released. Hopefully Jamf will take the Office 365 16.17 versions up into patch management soon!
https://www.jamf.com/jamf-nation/feature-requests/7850/patch-management-microsoft-office-365-16-17-x