Long range uppercuts should you thro them like a long range hook or more like a cross

[OMGWTF]

Does a long range uppercut unravel like a cross or does the elbow stay locked in position from start to finish?

If the punch started with the elbow in the final position you could not generate power and would be compromising defense horribly.

true that's a good point but does it become locked at the elbow once it reaches the desired arm position?