A serious question.
He was the major new face on Hickman's Ultimates.
In those early issues we learnt that the original Captain Britain, Brian Braddock, was in a coma. Seemingly dying from cancer, caused by the early suits his father had created for the EDI super-soldier program.
So in steps older brother Jamie, to take over his brother's mantle. He became a full member of The Ultimates, was featured heavily in preview art for the relaunch of the series, and even had a cover to himself. It was clear Hickman had plans here. He'd previously used Professor James Braddock and Brian in his Ultimate Thor mini. There was clearly something in the pipeline.
He and Spider-woman both got taken out by government agents, during The Children/The City arc, whilst off-duty. But since then?
He's not reappeared at all. Spider-woman has, but Captain Briain has vanished. He's not even been mentioned in Sam Humphries' run so far.
What a waste of a truly awesome character. Jamie's a crazy screwup in 616 continuity. Having him actually doing something with his life in the Ultimate Universe, and swapping places with Brian, is the kind of thing the Ultimate Universe does well.
I know that The Ultimates has become VERY American centric under Humphries, but I still think there should be a place for the guy. Kind of weird that he just... disappeared.