Not sure if it's been publicly stated, but I can't see a way to fit a mix of 196 seats consisting of 20 36" F, an unknown number of 34" MCE and standard Y without reducing the Y pitch.
Just adding another row of F would remove a row of Y and take us down to 185 (20F/165Y) total seats. So, now how to convert 29 rows of 165 30-31" pitch Y seats into a mix of 176 MCE + Y seats? Reducing 2" from all 29 Y rows gives them about 58" more room to do this. If they want MCE, they will have to trim down the Y pitch. I don't imagine there will be many MCE seats with this seating volume. Maybe they will just continue to just be the exit and bulkhead rows.
The 321neo will have more usable space for coach seating with the elimination of Door #2 and the added overwing exit. All of the current open space around door #2 gets allocated to Y seats.
https://mk0runwaygirl0t0gjwt.kinstac...age-Airbus.jpg
https://runwaygirlnetwork.com/2018/0...-a321-configs/
Obviously, this won't be the case on the legacy A321s in the fleet.