Last week, we reported that Apple has begun development of the successor to the upcoming OS X Mavericks: OS X 10.10. We reported hearing that the future operating system is internally dubbed “Syrah” (a type of wine), and now we have received evidence of the codename. Above is a screenshot of operating systems available for installation by Apple employees internally. As you can see, “Syrah” is available as an operating system newer than Mavericks and the recently released OS X Mountain Lion 10.8.5…

While we reported earlier that Apple is targeting a redesign of the OS X interface to mimic iOS 7’s new look for OS X 10.10, the current nightly builds are said to be nearly identical to the Golden Master version of OS X Mavericks. It’s unlikely that 10.10 seeds will gain new user-facing features or interface elements until well into development. Apple software engineering teams typically work on several projects independently, then pull them in all-together into the new operating system ahead of seed milestones.

Emphasizing the fact that OS X 10.10 is still very early in development is its current build number. We’re told that OS X 10.10 has seen approximately 30 seeds so far in development. For comparison, the first OS X Mavericks Developer Preview was build 476, while the first OS X Mountain Lion and Lion Previews were build numbers in the 100s range and 400s range, respectively. Nonetheless, it is likely that Apple is targeting a release of OS X 10.10 for sometime in 2014.

As OS X Mavericks moved to Golden Master status (the state in which the OS is ready to ship and/or be installed on new Macs), Apple moved a fair portion of its Mac software engineering resources onto 10.10. Other people on the team, however, are said to be working on updates to the OS X 10.9 Mavericks track. Apple is said to already be closing in on a point-release update (OS X 10.9.1) to Mavericks with bug fixes and perhaps the ability to block iMessages and FaceTime calls from certain users.

OS X Mavericks is on-track for release in the later half of October, and it will be available via the Mac App Store. Apple is yet to announce a release date or pricing information, but the company is holding an earnings conference call on October 28th. Historically, Apple has provided final release details for its new operating systems during the prepared remarks portions of these financial announcements.