As we reveal in issue five, the limits of Captain Britain's powers are now tied into his emotions. So if he's feeling very determined and confident, then he's very powerful, but if he's losing it then he'll really be losing it. He's as strong as he used to be, and he can fly, and that's all due to his magical nature, not to his costume. I've always seen him as something like the Shazam Captain Marvel, a hero formed through magic. Which means the subjective nature of what he can now do feels apt to me. As he himself says about great feats depending on whether or not he can gather all his courage together, he says: "well, I am Captain Britain."