I've opened thousands of iPads and very rarely are they over 90% ( typically in the 80s ).I was kind of surprised to see a full battery when I switched it on. A quick check revealed that it was manufactured the last week of February, so I'm impressed it kept the charge for over a month.
Nice... sure wish mine would arrive so I could put them on the bench.My 2017 iPad came with 83%. I am not sure whether it is recommended to fully charge a device you dont know how long it will be in a shelf. I am sure Apple charges their iPads to around 85% before they get boxed as you shouldnt fully charge lithium ions battery if it is not going to be used for an undetermined period of time.
Regarding battery, I am absolutely amazed by this iPad. I've been getting 14 to 15 hours usage time!