I seriously doubt it. It's at J0 as well, the most expensive bucket. I can't imagine why they'd have an extra seat but would be unwilling to sell it to someone willing to pay the full J walk-up fare.

Having said that, that doesn't mean a BF seat won't open up for other reasons, such as cancellation or no-show. I was going to say "or missed connection" but I doubt that TLV is a big connecting point.