Well... I believe mine came with the original firmware:
2015.9.3 - Version: v1.1.30
I did the "Christmas FW update" about a week after it came out:
2015.12.22 - Version: v1.3.50
I noticed that my range decreased and signal became much weaker after this update.
Last week i updated to the newest FW:
2016.3.15 - Version: v1.4.60
Surprisingly, it improved my range and quality of signal and wifi video down link. ( a lot of other P3S owners also confirmed the latest update improved signal/distance).
Here is a pic of the sticker from the box, i got mine around Christmas last year.. im not really sure how to tell the manufacture date tho. Maybe you can look at yours and see if there is any difference.
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