After market support is pretty limited, at least on Windows tablets. I think Cube i7 Stylus never had Bios update releases, though apparently later batches had updated Bios version. XDA had developed who made customized BIOS for I7 Stylus, but no I7 Book.
I think all we can do is compare if owners of newer units have updated versions of Bios.
edit. Its cheaper for a reason 😉