Totally by chance my HKG-TPE were swapped to the very same 33A. In both case cannot select row 11 & 12 online.
HKG>TPE I tried ask during bag dropped. Was being told both rows are full, not sure is it true but at least the 2nd half of the regional J section are completely full
TPE>HKG I ask during bag dropped again, after the agent phone call someone I got re-assigned to 12K. It turns out out of 8 seats in row 11 & 12 only two passengers including me, while the remaining J not full as well (around 50%-ish)