Thanks folks. I guess I will wait to see if anything is offered at checkin, else I will buy up before check in.

The crazy thing is that I have booked this via AF. Am a DL elite. And am flying KL metal and connecting to DL metal!

Had to call AF to ensure that the seats I was able to select on KL and DL's sites were what I wanted and they confirmed that I could have those.

So hopefully it will all go smoothly.