Easy. Bucky had an interesting definition of the word if he thought that was going to be anything Steve could explain. Then again, compared to anything else he was going to have to tell his friend, maybe that was the easy part.
He recognised the shell shocked expression on his friends face. He'd had the same one on his face the day Nick Fury had approached him in the middle of a completely changed New York. It was the expression of a man who saw what was right in front of him, faced with the challenge of accepting it as reality.
"Short answer is I don't know. I wish I could give you more, but I don't have it. A few of us wound up here a handful of weeks back and more have been arriving since. You showed up around the time I did." Something else he was going to have to explain. Somehow. "I don't know how it's possible, but it's like you've been replaced with an...earlier version of yourself." It sounded ridiculous even as he said it.