All this endless debate is going nowhere...apart from getting two posters' teeth on edge.
The 2000m+ fresh up issue has to be variable and contingent upon the horse's state of fitness/lack of at the time of entering a training programme proper.
As Bid has stated, possibly 4 months for an educated horse, but presumably, said horse has been spelling out at grass. If, as is wont to be done in the UK, the horse is kept up and walked or trotted daily while resting, then of course, the situation is very different. If the horse has been injured, with a very long rest, then a slow rehab, then, the time frame varies again. But the marker as to when that horse enters a regime of cantering/fast work could be considered to be the 'start' of the prep.
I have seven returned to training late last week. Three were race/trial fit when summarily forced out, another one as fit but not seen out.
Two of the three had race placings in that last week, one over a sprint distance, the other over 2200m. The third horse was a 1600m trial winner. I have every confidence that those four will be ready to do themselves justice - given suitable track conditions for one in particular - but if there is no option for 2000 plus, then two of those four will be disadvantaged.
Of the other three, one had been out spelling already, the other two had had a month's work and then out again. They will, of course, take longer to catch up with their stablemates.