How to clone a eMMC on RSB3810

I was exchanging emails with the local Advantech team, but they have stopped responding.
We are currently working on a mass production development project using the RSB3810.
Is there still no established method for duplicating the existing environment from one RSB3810 to another, or is there no plan to develop such a method at all?

At the moment, we connect to the network to install additional required packages from scratch, but this process is highly dependent on network connectivity and is quite cumbersome.