ZDNet’s Mary Jo Foley has confirmed recent rumors that Microsoft is delaying the fourth major Windows 10 milestone release—currently codenamed Redstone 2—from late 2016 to early 2017. The new date is timed to a coming wave of new Microsoft Windows 10 hardware, Foley says.

Coincidentally, I just discussed the Windows 10 release schedule inNew Windows 10 “Redstone” Features Are Revealed in Latest Insider Build this past weekend. In that article, I noted that Microsoft followed up the original July 2015 release of Windows 10 (retroactively renamed to Windows 10 1507) with the 1511 milestone in late 2015, and will follow up both with Redstone in mid-2016. (We’re currently testing Redstone in the Windows Insider program for PCs.)

What I left out was Redstone 2, the fourth major milestone for Windows 10. This was originally expected in late 2016, meaning that Microsoft was basically on a schedule in which Windows 10 would be refreshed about every 6 months. But now Redstone 2 is being delayed to early 2017, a full year after the first Redstone. Why would that be?

The culprit is a “new wave of Microsoft-branded Windows 10 devices,” which won’t arrive until early 2017. That is itself interesting, because the last wave of Microsoft-branded hardware ostensibly arrived in October 2015, with the Surface Pro 4, Surface Book, and Lumia 950 family.

But here’s the thing: Did those devices really “arrive” in late 2015? Remember that Surface Book was available only in the U.S. and Canada at that time and is only now starting to head out to the wider world. And that both Surface Book and Surface Pro 4 were buggy/unreliable enough at launch to justifiably avoid them until now, that they’ve been fixed with a major firmware update. And that the new Lumias, well … the less said about those disasters, the better.

Does this mean Microsoft won’t ship more first party hardware in 2016? I doubt that. The Surface 4 is widely expected any time now, despite the fact that not a single credible rumor has ever emerged. And we’ve been discussing a Surface phone for what feels like forever. Should Microsoft OK such a device, I can’t imagine it doesn’t ship later this year, potentially alongside refreshed Surface Pro and Surface Book devices. Perhaps that “new wave” of products is literally new. Something that requires or is at least based on Intel’s Kaby Lake architecture. (Maybe it’s time to read up on Kaby Lake for clues.)

It’s fun to speculate. But I think it’s fair to recall what happened with Surface Book and Surface Pro 4, and note that Microsoft was really stung by jumping into the future with Intel’s Skylake. Perhaps the software giant isn’t too keen to be first out the gate this time around. And besides, the current devices are pretty great now that they’re working properly.

Finally, it’s interesting how little a role Windows 10 plays in this conversation. We’re talking about a fourth major milestone release of Windows 10 here, apparently, but no one seems to know what features it will have, or what the point of this release even is. Tying it to some coming generation of Microsoft hardware is only part of the story, of course, since Microsoft’s hardware is only a tiny part of the PC market. Surely, there’s more to Redstone 2 than new hardware support.

Surely.