Just what’s said on the matter so far.
This is for the “regular” Sense version of HTC phones. GPE versions are a slightly different thing.
Will my HTC phone get it?
So far, HTC have mentioned One M7 and M8. That’s it for right now. And for “select phones” later on. That’s it. That’s the information you can get. I think that HTC want to play it a bit “safe” and not say something that they have to retract later.
— HTC (@htc) November 4, 2014
90 days from November 4th 2014 is February 2nd 2015. A guesstimate is around end of January. Or so. Depending on where of course. On network branded phones: might be a later date, since this is when HTC will be done, not when network will get it out.
More about CID here, which tells you where you get updates from
And HERE for previous things on this.