Microsoft may have only 
just announced Windows Phone 8 Update 3, but the company plans to start delivering it to developers later today. After 
over a year in the making,  Microsoft is finally launching its Windows Phone Preview for  developers. The program will provide registered developers with early  access to Windows Phone 8 updates, bypassing the complex and lengthy  carrier testing process. Microsoft is specifically targeting developers  with this program, but for $19 a year any Windows Phone 8 user can sign  up and get early access to updates. Even registered 
Windows Phone App Studio developers will be able to get early access.
 Windows Phone 8 users that  are registered developers or have a developer-unlocked device will be  able to download a Windows Phone Preview for Developers app that enables  the early access to updates. There are no restrictions on phone type,  only that existing Windows Phone 8 handsets have General Distribution  Release 2 (GDR2) installed in order to upgrade to Windows Phone 8 Update  3. After the special app is installed, phones will then update through  the normal software update process. While this is the quickest way to  access updates, and is similar to how Apple provides early access to iOS  developers, Microsoft warns it may void any warranty with a mobile  operator or device manufacturer.
 You may have to trade your warranty for early updates
 
If a Windows Phone user opts  to install the pre-release updates then they'll have to wait until the  update is released publicly to be in a "released state" as there's no  way to restore back to an older version of Windows Phone 8. The  pre-release updates only contain Microsoft's portion of the update, and  the software maker isn't rolling out any firmware or driver changes  alongside its own OS update. Today's update will bring 1080p display  support for unreleased devices, rotation lock, a new Driving Mode, and  much more.
 Microsoft isn't detailing  how it plans to handle future updates through the Windows Phone Preview  program, but it's possible the company may take an Apple approach and  place developers under NDA to provide early access to upcoming updates.  Today's announcement is focused on allowing developers to test apps on  real devices ahead of the OS update roll out over the coming weeks. It  also provides Microsoft with a way to address the growing frustration  over carrier delayed Windows Phone updates. Enthusiasts now have a way  to update their handsets
 before AT&T and others have finished testing the software. It's a win win for both developers and Windows Phone users.