JQ Seat Selection

[Peter JB]

I'm flying JQ this week...and I have already chosen my seats online. Of course the exit rows are never available to select so my question - who gets them? If they cannot be selected online, what if the plane fills up in bookings, are they made available then to the last 12 bookings because everyone else has taken all the others (assuming naturally that every person has booked all other seats online AND have chosen a seat)? The dangerous part of this of course is that children will be in the last 12. So I'm interested in how that works.

Whilst I have booked, if I get to check in early enough, can I request the exit seat and therefore swap for my already booked seat?

Interested to hear any thoughts on this.