WKExtendedRuntimeSession Health Monitoring

I am working on an app for monitoring activity in tremor patients over extended periods of time. This entails continuously recording from accel, gyro and magno for extended periods of time (ideally up to 12 hours) in the background. I have been able to use the WKExtendedRuntimeSession to record in the background for up to an hour, but is there any way to get even longer background runtimes (at least 4 hours, possibly up to 12 hours)? In the WKExtendedRuntimeSession documentation there use to be an item called "Health Monitoring" that supposedly had no time limit, but it is no longer there. I requested the special entitlement several times, but never heard back.