So, I got a used P3S last fall that has performed great so far (except for recently after the new firmware update, but that's another post). I see people asking sellers of these drones how many times the battery has been charged. Mine says 52 times. What is considered a high number? Today was the first time that I have flown the drone long enough for it to RTH due to critically low battery, I wanted to see if the RTH actually worked, is there a difference between charging a partial battery and fully running a battery down?? Thanks in advance