How is it possible that 2% of the battery was drained, even though I had the IPP 9.7 (256 GB, wi-fi+cel) in airplane mode? Is this something new? I thought my IP 4 remained at 100% when not in use, for days. Do I need to do something specific with the Pro 9.7? Also, the battery app says there is nothing wrong with the battery's health, it's brand new. P.S. Before I turned the IPP off (closing the Smart Cover), I had it charged to 100%.