I been having some lockup issues with the camera since I downloaded the latest firmware. Yesterday I removed the grip and camera battery, then replaced the camera battery which was fully charged without the grip. No apparent battery drainage issues after over 8 hours, then installed the grip with another battery in the grip. I just looked at both the in camera and grip battery, both have not discharged in 12 hours.
I received a prompt reply from Aputure and they stated that the grip could not cause the battery to drain when the camera was off.
This leads me to believe the camera or camera/grip combo may be the cause, and may be related to the camera lockup issues. I'll let them sit another day and see if anything changes.