Hey! Sorry to get back to you so late, seeing as I believe we covered these topics in our email conversation.
The 8 hours charging time before first use it simply to ensure the battery is fully charged and to calibrate it properly.
Charging more than 8 hours will not hurt the battery as the charging turns off automatically when the battery is full. In other words, no need to set your alarm!
I hope this helps.
Maxence
Aodyo Instruments