Hi there,
I understand your frustration but sadly, like nearly all of the user's on this forum, I have no power to influence Gigabyte or their decisions when it comes to BIOS updates which is why we recommend that you keep contacting Technical support as they are the only ones who can do anyting about this.
I know you won't want to hear this but, you should also remember that core unlocking is not guaranteed and I too have had CPU's that can be unlocked on different maker's motherboards but not always on Gigabyte boards. The general consensus is that Gigayte have set a higher threshold for core unlocking for a more stable experience if successful, which is why the failure rate seems higher than others.
Also, these boards are primarily designed for the AM3+ CPU's when they come along so the BIOS is probably geared more towards those than the current crop of AM3 processors.