Development continues on Windows Phone 8.1; final build expected April 14th

Last week, and ahead of the official launch of Windows Phone 8.1, we reported that Microsoft had reached the RTM milestone with its OS update, and that its code had been finalized ready for distribution to Microsoft’s partners. But it turns out that things are a little more complicated than that.

As we reported, Microsoft did indeed sign off on the Windows Phone 8.1 build – what the company refers to as “the final feature build” – on March 26. On the same date, that build – 9651.12349 – was made available to Windows Phone partners via Microsoft Connect.

But that wasn’t actually the ‘final’ build; indeed, WPCentral pointed out that a few bugs still needed to be exterminated in the OS, suggesting that this process was likely to take a couple of weeks.

An email shown to Neowin today, sent by Microsoft to its Windows Phone partners, now clarifies the timeframe that the company has set out for completing development of the launch build of 8.1.

The email refers to the remaining dev work as the ‘Final Adaptation Kit build’, which it says is intended to address “a small set of issues to improve the commercialization aspects of the product” (sure sounds like bug-fixes to us). Work on this is proceeding on schedule, and is expected to be completed on April 8.

The ‘final build’ from last week, combined with the more recent Final Adaptation Kit, will form the ‘real’ gold code for the OS – referred to as the snappily named ‘Windows Phone 8.1 QFE1 Final Adaptation Kit Build’ – which Microsoft will seed to its OEM partners. This code should be in the hands of manufacturers on April 14, before its rollout to existing users begins later this month through the Windows Phone Developer Preview.

The first new devices designed for Windows Phone 8.1 are not expected to go on sale until next month. Among the first handsets will be Nokia’s Lumia 630/635, while its new Lumia 930 flagship will go on sale in some markets in June. 

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You know you can RTM before being finished with development, right? There's nothing particularly needing clarification here. An RTM build just needs to be done enough for OEMs to test on without worrying about any significant changes. The definition of what an RTM build is seems to be muddled these days.

Good to see though, can't wait to get this update :D

spenser.d said,
The definition of what an RTM build is seems to be muddled these days.

Exactly, Release To Manufacturing. So that OEMs can start final product testing.

adding last minute small features perhaps? its amazing they had more than a year since last major release but they couldn't finish it ontime. it must have been due to major infrastructure changes such as universal app support and new packaging system. but its all good. I prefer to wait that getting something not finished. the whole WP7.x was a mistake. and it hurt Windows Phone reputation a lot.

Because those 10 unlucky bastard who are the so called "Windows phone developer team" sometime go on vacation, sometime on sick leave etc. You understand that 10 people cannot do miracle in 1 year, especially not, if code is developed at the usual in the Redmond area. But at least there will be not many features included, so less possible bugs!!

Let us know when you release some phone software, Mr. Code. I'm sure it will be MUCH better than anything MS has ever done. Douche nozzle.

ValaXx said,
why doesn't anyone talk about the developer preview and its release date?

If the bugs are expected to be done on the 8th, like they post in the article. Then the rumor so far of the 10th for developers to get it sounds possible. It could be anywhere between the 10th and the 18th I'd say, no way developers won't get it around the same time it goes out to OEMs.

If we're going to get new 8.1 phones out in May like they said then developers need that month to update their apps and or start work on the new universal apps that they showed off.