Finish up Flash's bio now just tying in Arrow-Verse Barry with this universe and thinking about it we can just have Barry living at the Manor. In universe his reason is simply because he feels the League need him there more than Central City does since Team Flash can hold things down there and he can always run back if they need him. As far as the CCPD are concerned Barry's taken some time off for personal reasons, that way if he ever needs to go there for his job and return to Central City in the story he can without having him constantly running from Central City and back again.