I had an existing 30A breaker with 10-3 wire. I capped the red wire on both ends and replaced the 30A breaker with a 20A beaker. At the end of the run (nothing else is tied to this wire/breaker), I want to connect 12-2 wire. Is there anything wrong with doing this? I understand that it is not best practice, but is there anything unsafe or against code
With this scenario?