That's a MASSIVE delta for such a high SoC.
You'll need the dealer to do a CVLI test but for the 40 kWh pack. Google for
site:mynissanleaf.com cvli. The voltage may be different than listed at
https://www.mynissanleaf.com/viewtopic.php?t=16070 since that was for the 24 kWh pack w/different cells.