After the decision to provide Windows Phone 7.8 to existing Windows Phone 7 users, instead of a full Windows Phone 8 upgrade, Microsoft is now unveiling the support dates for its latest mobile operating systems. The company has previously shied away from support timelines for Windows Phone, only mentioning a brief promise of 18 months at the first unveiling of Windows Phone 8, but recent lifecycle updates confirm support dates until 2014. Windows Phone 8 will be supported, with security and other updates, until July 8th, while Windows Phone 7.8 will continue to be supported until September 9th.

An 18-month support plan, but what about upgrades?

The dates mean both operating systems will be supported for 18 months after they originally started appearing on devices. Microsoft makes no commitment to promising updates for every device though, warning that they're controlled by carriers, regions, and hardware capabilities. There's also no mention of update availability to the next major version of Windows Phone for existing users. There was a considerable amount of backlash over Microsoft's decision to axe upgrades to Windows Phone 8 for existing devices, but with a big kernel upgrade in place we'd expect that Windows Phone 8 devices will be fully upgradeable to the next major version despite Microsoft's non-committal. Whether or not devices receive a future OS upgrade will likely be controlled by OEMs and carriers.

Microsoft has previously revealed that the "next release" of Windows Phone, codenamed Blue, is expected to be made available in the holiday season. The software maker is pushing out smaller feature changes until that time, with a recent "Portico" update adding a number of tweaks and settings that are all part of Microsoft's 18-month support cycle.