Image on top shows the current 400mm f/2.8 GM
From what I got the new $14,000 600mm f/4.0 FE will not be on the market any time soon. The people who reported to me about this lens had not chance to test it and it looked like this was more of a development announcement from Sony just like it happened with the 400mm GM lens.
On the other hand the 200-600mm FE preorders will open 1-2 days after the announcement on Monday. Shipment start sometimes in July.