I get a lot of questions about when Microsoft is planning to launch Windows 10. I'm sure Microsoft execs do, too.

In this photo from September, Microsoft Operating Systems Group chief Terry Myerson unveiled the initial Windows 10 roadmap. This week, Chief Operating Officer Kevin Turner elaborated a bit on that roadmap.

On December 4, Turner covered Windows 10, along with Microsoft's evolving business model, during his appearance at a Credit Suisse Technology Conference appearance.

Turner told attendees that Microsoft is still on track to "talk about the end-user consumer experiences in the early spring" of 2015. He also said Microsoft will have a "developer preview" in the early summer.

"And then by next late summer and early fall we'll be able to bring out this particular OS. That's the current plan of record."

Turner's timeline is mostly the same as the somewhat vaguer one that OSG chief Myerson shared back on September 30 with those of us invited to the "chapter 1" Windows 10 reveal event in San Francisco.

The image embedded above in this post is of Myerson and the Windows 10 timeline he showed us in late September. That image shows some kind of consumer reveal in the early part of 2015; a developer reveal event after that and then a "launch wave" around mid-year.

Microsoft is going to show off the January Technology Preview of Windows 10, as well as a first preview of the Windows 10 mobile SKU that will work on Windows Phones, ARM tablets and Intel tablets in late January in Redmond, according to my sources. The mobile version of Windows 10 is not expected to include a desktop as part of the OS, while the current "desktop" version of Windows 10 that is in preview does and will when it ships.

Microsoft officials also have said that Build 2015, the company's main Windows developer event, is coming the last week of April in 2015.

I don't know what Turner meant by a Windows 10 "developer preview" coming in early summer, since the company's new strategy for delivering test builds calls for Microsoft to deliver regular (monthly or more) updates to Windows 10 for all interested testers. I wouldn't think there would need to be a separate developer preview given that new scenario. I'm going to assume he just meant Microsoft would go public with more about its universal app/developer strategy at Build by his remarks.

Windows watchers may recall that for more than a year, our tipsters have been saying Microsoft's internal timeline called for the company to release Windows 10 (then known as "Threshold") in the spring of 2015. But in September, Myerson made it sound like late summer/early fall was the "official" delivery ship target.

Also: For those wondering about when Microsoft will debut the Metro-Style/Windows Store touch-first version of Office that won't need to run in the Desktop, my bet is that will arrive around the same time as Windows 10. Microsoft officials have said that the desktop version of Office (Office 16) will be available in the second half of calendar 2015. My sources have said the touch-first version will be available the same time that Office 16 is.

Turner didn't address Office timing in his remarks yesterday.