If I shoot, use VCP during and then recover after, can I then use it again when I am attacked? I think so because it isn't an action of any kind.

Yup! I had played a build using shells and VCP with exactly that strategy. Shoot, using shells and VCP on offense. Recover both cards. Use VCP again on defense later. And then it automatically readies at the end of the turn to do it all again.