BIOS video routine question

I was looking at https://singularity.svn.codeplex.com/svn/base/boot/SingLdrPc/blentry16.asm
and I'm confused by the BlInitializeVideo function.
Particularly this call to the bios video routines:
        mov     ax, 1202h       ; LINES_400_CONFIGURATION
        mov     bx, 0301h       ; SELECT_SCAN_LINE
        int     10h

That code sets AH=12h, AL=02h, BH=03h, BL=01h, right?
From the comments, it seems to be calling Int 10/AH=12h/BL=30h, listed here http://www.ctyme.com/intr/rb-0167.htm

Does anyone know what's going on in this code? Is there some funky bios thing going on or am I misunderstanding something?

>>3
Could you explain what I am misunderstanding?