I don't know. I have upgraded & downgraded, used the FW's from threads around the site & ended up with + at the end of the FW#. The current FW has no + at the end so it is possible it's downloaded it again for some reason. I've pricked about with it so much & gotten nowhere.
I would of thought something like this would be resolved by now. I don't know whether to sell the **** thing & look for an alternative. Has DJi said anything about this FW causing the range issue? & a timescale for a P3S FW update fix?
In brief this has been going on for over a year.
Phantom 3-Std Weak Remote Signal
It has happened to me twice, poor remote signal after firmware.
Here is a small lists of just that relation, all are Standards, none of are loosing video or telemetry signals.
Terrible signal performance
On the second time, Being able to download firmware option had just showed up in the app. So I tried it again, successful it said, I did a flight test, it was bad again. I go back to the app, downgrade was not available, it was before I upgraded.
While mine was in for repair, stuff started showing up about putting the firmware on the SD card, since I got it back I have not done any firmware updates.
What I think, you and me has been reading on firmware fixes, is not the same maybe a 10-25 % change in performance. Not what I have seen is about a 95% performance failure.
I have many post on this on this forum, and read many more, just on this problem. I am now convinced again with your posts and a few others lately, that there is a hardware failure on these firmware updates that is not reversible.
First failure, returned different phantom, different remote.
Second failure, returned same phantom, different remote. Phantom had some repairs / replaced parts inside. Which I have posted here, but I'm not at my main computer to do a quick search of my book marks.
Yes, been frustrated.
Can't downgrade Firmware
Rod