I do not blame DVC for making the change. I do hold them responsible for the abruptness of the change and the lack of the communication in regards to it. There was no communication or warning whatsoever.
Disney Vacation Club has every reason to facilitate the wants and needs of the members it serves.
It seems clear that this change was forced upon them and they had no choice but to comply. If DVC had the power / authority to give its members a grace period or a heads-up to add the segmented DDP, why wouldn't they? Disney Vacation Club has no stake in revenues from the Disney Dining Plans.
I somewhat agree on the lack of email / website notice but that wouldn't have changed the situation.
Do you recall any formal announcement from DVC that it existed in the first place?
No, I don't believe so.
I first became aware of it from a conversation about the computer system upgrades. DVC was very forthcoming in detailing (to me) how members would be able to segment the trip into what they called multiple "Accommodations"--some with and some without a dining plan. And for the most part they have accommodated nearly unlimited configurations over the last 11 months.
But no, it was never explicitly communicated to members via the website, Disney Files or any other method I can recall.