I've voted 576 as well. All my GH campaigns have started in that year. I've always lifted tons of stuff from later materials, but never really adopted the official timeline.Voted for 576, but with the caveat that it would be the Ghosts of Saltmarah soft refresh version.
I would bet on all of this.I think it'll receive a similar treatment as FR did with 5e - the timeline will be moved forward, but the setting feel and details will be changed to be more in line with earlier versions. I'm not talking mechanics (I fully expect dwarven wizards and tieflings to appear, and happily), but they are more likely to move things back to how they were before From the Ashes in feel.