Hi and welcome to the Gigabyte Forum.
The graphics card section really don't seem to like giving any updates or details away really. It has been a long standing issue from my viewpoint.
I wouldn't advise using the firmware from another card even if it is basically the same as that the best of outcomes would be that you would lose all the overclock that comes as a part of your card. It could be much worse.
I think it is best to wait for an answer from GGTS and hopefully they will be able to supply you with an up to date firmware for the card.