Microsoft plans to focus on improving the devices at hand, rather than announcing a new version of Windows Phone months before it actually ships, an executive explained at Mobile World Congress 2013. 

Microsoft senior marketing manager Greg Sullivan met a group of reporters to talk Windows Phone 8's upgrade strategy, according to PC Mag. There, he revealed that Windows Phone 8 will be upgradable - a cycle that has been strongly rumoured in the past. 

"We're going to have an upgrade path going forward. Windows Phone 8 can evolve. We have an architecture that enables portability and is fundamentally hardware independent," said Sullivan. "As the market evolves and customer requirements demand it, we'll evaluate options." 

The upgrade path is said to revolve around"'Windows Phone Blue" that will come sometime in the summer. Rumours have suggested it will bring several user-interface enhancements and kernel updates to provide a better experience. Sullivan didn't specifically confirm Windows Phone Blue details, but given his comments, it seems the update is logical.

Before the major Blue upgrade, Microsoft is also said to be releasing WP8 GDR2 as early as mid-May, rumours have suggested. According to ZDNet, there is even a third update in the pipeline for later this year. 

Even though Microsoft won't announce an overall new version of Windows Phone any time soon, Sullivan said: "Over the course of the next several months, I wouldn't be surprised to see some exciting new devices."

The HTC Tiara, featuring WP8 GDR2, is believed to be one of those.