500 stops divided by an allowable 14 hours equals slightly over 36 stops per hour, every hour, for the entire day. Factoring in to/from building time, AM/ PM time, paid breaks, vehicle pretrip etc. it would require an average of something like 40 stops per hour to be maintained while on area.
The only way that is even physically possible is to have multiple stops for entire apartment complexes being DR'd into one central location like a receiving room, with credit being taken for each stop and no attempt made or delivery notice left at each door.
It would also require a complete and total disregard for all pertinent Driver Release methods we are expected to follow. You would literally have to toss packages out of the car onto porches as if they were newspapers, without bagging them for weather protection or making any effort at all to hide them.
I'm not doubting that the OP was able to make 500+ stops show up on his report in one day; all I am saying is that he did not do the job in anything like the manner that is normally required of us and that his results could only be duplicated under conditions that don't normally exist in the real world.