BGR has exclusively learned that HTC plans to unveil several upcoming Windows Phone Mango devices at the company’s upcoming event taking place on September 1st. While Android is HTC’s bread and butter of course, our source confirms that Microsoft’s latest Windows Phone OS, Mango, will be the star of the show this time around. We have heard HTC will specifically be unveiling the HTC Eternity, a Windows Phone with 3.7-inch display headed to AT&T, in addition to the HTC Omega, a 4.5-inch Mango phone that is headed to T-Mobile USA. We don’t have exact launch dates at the moment, but we’re told that they could come sooner than expected. HTC declined to comment.