I don't think the FA cares much about when our season starts, who is our manager, the uncertainty fans feel etc.
They will do their investigation in their own tempo and when they damn well please. The verdict will be ready when it is ready.
If that is before preseason, the start of the season or some time after the season has started means nothing to them and they feel absolutely no need to come out with updates along the way. It will drop like a bomb when it does (or it might get leaked right before).