Firmware downgrade of RBR750 from V4.6.7.13 to 3.x

[skuhn]

I updated my firmware on this weekend from a 3.x to 4.x version. This lead to back-haul problems with the satellite. It's working after reboot for a couple of minutes and then starts to blink white until I unplug it. Since nothing else changed in my home this is clearly related to the update.

So I want to downgrade the firmware again. This worked without problems for the satellite, but if I do it on the router it doesn't work. When I try to run the firmware update I get following

Steps I did to make the update:

1) Download the firmware (multiple times and multiple versions 3.x and 4.x to make sure there was nothing bad)

2) Unpack it

3) Upload it

4) Enable the yes button via dev tools

5) Click on yes

6) It fails with the above error

Is there anything I can do to make the downgrade of the router work?

[FURRYe38]

First off how did you update FW to v.13? Manually or Auto update? Manually is recommended.

Did you first update the RBS then RBR? 

Is the RBS wireless or wire connected to the RBR? 

What is the Mfr and model# of the Internet Service Providers modem/ONT the NG router is connected too?

What is the size of your home? Sq Ft?
What is the distance between the router and 📡 satellite(s)? 30 feet or more is recommended in between RBR and RBS📡 to begin with depending upon building materials when wirelessly connected.
https://kb.netgear.com/31029/Where-should-I-place-my-Orbi-satellite 📡

What channels are you using? Auto? Try Auto and 48 on 5Ghz. Or try setting manual channel 1, 6 or 11 on 2.4Ghz and 40 to 48 channel on 5Ghz.
Any Wifi Neighbors near by? If so, how many?

Downgrading to v3 FW is not supported. 

[FURRYe38]

That downgrading FW is not supported thus NG remove the ability to downgrade. I don't know the reasons why. 

[FURRYe38]

The Orbi systems are complex and I presume that there may have been some deep FW changes and such that NG found would cause problems in downgrading system. Early v4 versions we all know are bad. I've had good operation in past two versions of FW. 

[Rudolphy]

No problems for me either, my system runs smoothly in AP mode at .13