I have not called it a ‘daring’ move. I have just given my suggestion that it is not required.
You are calling it a ‘daring’ move. If you have the money to spend, you can go ahead and file for EB3 downgrade right now without waiting. Its your choice.
When you file EB3 i140 to downgrade from EB2, you are asking USCIS to use the EB2 i140 dates.