My date has been between February and August 2019, for some time. Unless there is the smoking gun to end all smoking guns... the kind of thing that would wrap this up in a weeks time (from the smoking gun becoming known to his removal), it's going to be tortured and protracted process. Republicans being battered during the 2018 midterms at the State and Local level (which matter so much more than the House or Senate in 2018 due to the coming 2020 census and redistricting) is a pre-requisite for his removal.
But that said Trump is WAY ahead of schedule. His alienation of Republicans the past couple of weeks has been monumentally important, and not something I expected to happen until next Summer.