New cases are generally annealed at the factory, yet not all exhibit the "annealed color" like Lapua cases for example so I'm not sure that color is a good indicator.
Most ALL cases are annealed as the final step after forming. The telltale annealing ring discoloration comes right off with a bit of tumbling and/or acid washing.
Annealing is linear based on temperature. There is some degree of softening and recrystallization of the brass structure once that threshold is reached. Best I recall that's around 465�, and it gets softer and softer until it goes dead soft up around 1200� where it's ruined. (Don't have the exact temps off the top of my head.) In between there the extent of annealing varies with the temperature. So, you can have no annealing ring and still have some sufficient softening to prevent splitting the necks.
