Originally Posted by AbigailG

So I don't have personal experience with this but the general consensus seems the be that if they release an additional seat it will be close in (2-4 weeks).

I'm currently trying to get a third ticket for a family trip. I was able to book two in J returning in F and then one in F returning in J shifted by one day. (In case you are not familiar, it is super easy to change the date online if another seat becomes available.) My hope is that since 2 J seats and 1 F seat were released on the first flight they will release 1 more F seat close in. And similarly the return flight released two F seats and only one J.