Redmond is a major leaguer next year, not AAA depth - assuming that the poster is correct who said he is out of options.
If he's on the forty, and he's out of options, he can't be sent down unless he is DFA'd or on injury rehab, as I understand.
I highly doubt the Reds will start Redmond in the rotation. He has no major league experience starting and this doesn't make sense to me on a contender.
More likely he will join (or replace?) Simon as a longer reliever, who can back up as a starter. Maybe Lecure gets promoted to set up man.
Reds now have a bunch of righty MLB relievers on the forty. Arredondo, Hoover, Lecure, Masset, Ondrusek, Redmond, Simon. Assuming two lefties, two righties will have to go.