"this agreement will not obligate funds at the time of award"
Well that would be a bit brain-dead on the part of the DOD. Obviously the funds will be paid out in return for actual acquisitions, otherwise there is a very large window for error, honest or no.
Still, some champagne will obviously be opened in the marketing departments of the six companies, because hey, that counts for this year's bonus !
Trying to lock in licensing?
I'm wondering if Microsoft will make exceptions for governments, but my guess is that DoD wants to get their deal done now to ensure they get the last perpetual versions of Windows, Office and the servers/applications.
Microsoft isn't showing any signs of slowing down on the whole Windows as a Service thing, and setting Office 2019's EOL date the same as Office 2016's is a major clue that they're not going to be rolling standalone versions of these products very soon.