The Leaf Spy numbers (AHr, SOH, and Hx) typically dropped on my 2015 if it was driven gently and charged with L1 or a low-rate L2 EVSE. The numbers would then improve with highway driving and high-rate L2 or DCQC charging. I did not notice that with the 2011 (original battery chemistry from Japan) and have not yet noticed that with the 2019.
Silver LEAF 2011 SL rear ended (totaled) by in-attentive driver 1/4/2015 at 50,422 miles
Silver LEAF 2015 SL purchased 2/7/2015; traded 8/10/2019 at 82,436 miles
White LEAF 2019 SL Plus purchased 8/10/2019