I think the staff do not always know what they are talking about. I have generally been able to get the first row in economy via OLCI at very close to T-24 hours most times.
It is only a small percentage of flights where it takes me a while to get the first row of economy or not at all....
Well thanks to you JohnK, I have been checking "Select Seats" everyday and always find new seats more forward. So I have ended up from a 70's to a 66 and now to 54... now trying to get more forward (Middle aisle I want) so these are scarce