Which version do I require?

[Nicoletta]

Reading through the instructions here says;

Starting with Asus's 3.0.0.4.380_3000, a new firmware format is used. To flash Asuswrt-Merlin on one of these newer firmwares, you will need 380.61 or newer. Likewise, downgrading to an older version is not supported. (Try firmware recovery mode if you really need to downgrade.)

and

The RT-AC68U and RT-AC56U need to be at least on firmware 378.55 (or the last 378.xxx version from Asus) before you can flash 380.xx, due to the partition size change.


Since my Asus stock firmware is version 3.0.0.4.385_20585 I will need 380.61 or newer. But it also says that I need to be at least on firmware 378.55 before I can flash 380.xx.

Should I flash 378.55 first before everything will start working on 384.18?

 

[ColinTaylor]

You don't need to flash any older versions. You are currently on version 3.0.0.4.385_20585 which is a 385 version. That is much newer than the 378 and 380 versions you were talking about.

Just flash the latest Merlin release directly.