>>28493974This.
I think legally you’re supposed to signal like 100ft before you make the turn or lane change.
But then there’s the real world, you’re driving on I-95 in a semi truck and everybody is an asshole. If you need to change lanes driving the truck and you put on the signal, the car in back will close the gap 75% of the time because they don’t want to be behind a truck. So in that case, signal as my tires are coming over the line.