Specifically, owners of the HTC 10, U11, and U Ultra will receive the update, but there’s no word yet on when these updates will come. We could speculate on when you might see it (maybe by end of 2017?), but that isn’t very helpful to anybody.
Specified HTC owners, prepare yourself for the sweetness of Oreo.
We're excited to bring Android Oreo to HTC U11, HTC U Ultra, and HTC 10 owners worldwide! Details & additional devices to be announced soon.
— HTC USA (@HTCUSA) August 22, 2017