First come first serve by legal means. I know on publc land where I hunt it is illegal to hang a stand this time of year. Some smart A$$ think because he sets his stand mid July that it's his spot. I disagree. I'd get the gps coodinates and let the warden know of you find. They will take the appropiate actions.

1st come 1st serve is fine so long as your not breaking the laws and denying others a legit shot at 1st come