Seat map closed (& good Y seats on a 343)?

I chose my seat online for my JFK-LHR flight (later this August) a while back, and now the seating map is closed. Is the seat I chose still reserved? I can't seem to find any indication of what I hoped was my seat reservation.
Also, any thoughts on better-than-average (or worse-than-average) economy seats on a 343, besides what seatguru tells me? (And can I choose exit-row seats at OLCI?)
Thanks!
Also, any thoughts on better-than-average (or worse-than-average) economy seats on a 343, besides what seatguru tells me? (And can I choose exit-row seats at OLCI?)
Thanks!