As you've read in my previous news-item, almost everything is already known about the 7T-series. For example, their design and their specs (for both the 7T and 7T Pro). Now, Pete Lau, the CEO and founder of OnePlus, made a post on the OnePlus Forums that the OnePlus 7T-series will officially be announced at the 26th of September in India. European launch will follow later, at the 10th of October.
Source of the post from Pete Lau: https://forums.oneplus.com/threads/introducing-the-oneplus-7t-series-launch-event.1104383/
As European or American, you can win a ticket to the launch in London
OnePlus also announced a contest for you as European or American, where you can win a trip + ticket to the launch in London. You can read more about it here: https://forums.oneplus.com/threads/win-a-trip-of-lifetime-to-eu-launch-ticket-giveaway.1098669/