Comment by Ecco

With a limit of 10 million different serial numbers, I wonder how China does it. I can't come up with a decent estimate, and maybe I'm way off. But with the growth of sellers like Shein or Temu, I wouldn't be surprised if they shipped that many parcels in like a single day ? Or at least in a timeframe short enough that they would have over 10 million shipped but yet-to-be-delivered parcels, effectively running out of tracking numbers.