Hi Alan,
I don’t execute No. 3 very much other than the few times I have tested it. Bending occurs at a certain spot when the key is slightly depressed. I am not sure it matters whether you get to that spot by coming out of a note (releasing the key to the point of bend) or starting a note (depressing a key to the point of bending). I only think of it as trying to find that perfect position where the note bends. On my melodicas, it is very difficult to find that spot and hold it particularly when my hand is in the normal playing position.
Regards,
Lowboy