While Microsoft hasn't yet announced the date nor the time for their E3 press conference (at least at the time of writing), Tom Warren, senior editor at The Verge, decided to share the info on his Twitter account. According to the tweet, this is the date and time for the Microsoft conference is Sunday, June 10th, 9pm GMT / 10pm CET
Also interestingly, Warren teased that Microsoft will be doing "something different" this year. "I think that 'different' element will start to make sense soon...", he concluded, perhaps pointing out to a coming reveal of some sort. Honestly, we have no idea what he's referring too, but we look forward to finding out.