I'm not sure what you're saying. The 20% Critical threshold assures me I need to get it in gear on RTH if I am manually flying. However, the AutoLand occurred within the first minute of flight because, as you suggested, the battery was not used for some time and was not fully charged.Why you might need to set your critical battery warning above the lowest available threshold is a mystery in itself however it is a big clue as to why the phantom wants to autiland earlier than expected.