Root Partition size with different amount of disks using ADP v2

[frail flame]

Hi everyone, so I understand that the root partition size is determined by the amount of disks present at initialization.
Is there a way to figure out how big it will be with let's say 20 disks compared to 40?
Also, is this universally the same across all supported systems, or are there different Root Partition sizes for different products?
It would be beneficial to know this to back up an argument when proposing a higher amount of disks.

Thanks

[hearty ermine]

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