Rooting Note Air 3. Is there a guide ?

Hi,

A few months ago, I rooted my Note Air 3, on firmware 3.5.4. I don't remember at all how I did it.

Now, I see that firmware 4 is available. OTA update from the settings fails.
I would like to first clean update to firmware v4, cleaning all data. And then, I want to root it again.

I have seen that Onyx made it harder to root by removing commands from fastboot. If I understood correctly, now the way to do is through EDL. I am not familiar at all with that method, so I am looking for an up to date guide.

I have found this guide for Note Air 4 which looks very complete https://github.com/jdkruzr/BooxPalma...main/README.md , but I don't if it is applicable to Note Air 3 too. So I would have the following questions:

1. Is this guide still valid for Note Air 2 ?
2. If yes, what will be different for my device ? What loader will I use, which commands will be different ?
3. If I want to clean update to v4 first and then root, how do I do it and when ?

Thanks in advance for any answer, have a nice day.