I saw this post here: https://www.reddit.com/r/leaf/comments/ ... a_40kw_to/
It sounded too good to be true, so I called Nissan EV Help. I just got off the phone and the 24 kWh battery replacement cost is now $5500, with the $1000 core charge, plus labor. That means that for around $5500, you could have a brand new 24 kWh battery with a full 5 year warranty on capacity and 8 year on defects.
In case anyone's got a badly degraded Leaf, you now have a decent option!