If someone does reply, I'd like to know can you mod a certain file and Odin in the bootloader section when flashing an update to ensure that you stay at a certain bootloader level while the other files such as AP CP and CSC remain intact from the sam mobile stock firmware.(which I assume the term combo firmware file originates)
My most recent encounters are the device and binary are not the same which I attribute to this problem.
To make one of my eMMC bricked phone fully bootable from sd card without using fastboot, I was interested to know the internals of uboot, lk and aboot, particularly for the working of fastboot, odin etc. But the web has got very limited material related to this. Keep searching and do share if you find something helpful.