Just throwing this out here;
maybe what he meant to say was “how he made a name for himself”.Han was already a fairly well know smuggler by the time of ANH, so this film might revolve around some big event that makes him famous in the criminal underworld. My guess would be some expansion on the Kessel Run as it hasn’t made an actual appearance in the new canon yet.
I hope it’s this. I would hate it to be that Han Solo is just his nickname.
It doesn’t have to be a nickname. People change their name all the time. Sounds like the kind of thing a smuggler might do. shrug