I've never seen any pre-announcements or schedules posted. There was a post by jimc where he talked with the devs at a conference they had a booth at. Stil pretty vague as to a timeline though.
We talked nothing about timeline. Im sure its done when its done. In the past the update have roughly been quarterly. Maybe this one will he 6mos....who knows. Id rather they take longer and get it right. If they are focusing on dual extrusion on this one, that cant be easy and i would expect it to be longer than the others to release.
Well would have preferred 1-3 bugfixes then a release, then a few more then a release, monthly.
Than 20 fixes 2-3 times a year.
And maybe more work on existing bugs than adding more weird printers and such.