gearbox oil level - 1999 A4

[opposite_lock]

Hi

Going to do a gearbox oil change. I notice that my manual says to fill to 7mm below the filler plug, but common practice (and some other guides I've checked) says just to fill till runs out the plug.
Does anyone know which is correct, or if it matters? I have heard mention that level is critical for some of the Audi boxes.

Thanks, Phil
Audi A4 Avant 1.9 tdi (110bhp), 1999
Manual gearbox

[a8 tech]

When it stops running out of the filler plug then thats fine.