If you've got a Surface PC that's enrolled on the Windows Insider Program, it's once again time to check for updates. According to Windows Central, Surface Pro, Laptop, and Book 2 are all receiving new updates.
Unfortunately, there's no way of knowing what exactly is included in the new updates, or what got fixed. Microsoft hasn't updated its Surface Update History pages just yet. It rarely does so in a timely manner, and the fact that these seem to be exclusive to Insiders on Windows 10 Redstone 4 means we're even less likely to find out anytime soon.
For the Surface Laptop, the date on the update should be February 28, which is also the date of the latest public update. However, the new version number is 135.2139.257.0, compared to the previous 135.2114.3.0.
We'll surely find out more about what's included in today's updates if they ever make it out to non-Insiders, including the exact names of the updates, what's included, what got fixed, and more. Expect to hear more in a few weeks.