Per AMD's announcement this week, several models of the RX 5600 XT were listed as update-able to 14 Gbps Graphics Memory Speed:
One of the models listed is Gigabyte's RX 5600 XT GAMING OC 6G, however after contacting Gigabyte support I was told the card I have is not compatible with the updated BIOS. There is no indication on Gigabyte's website that my card does not support the update. I was told that the BIOS update files listed on their website (and linked to in the AMD announcement) are not for my version of the card, even though there is only one model of this card released by Gigabyte.
I bought the card with the intention to update to the latest supported firmware. Since there is no differentiation in model numbers, there is no way a consumer can discern during purchase whether the card they are buying is update-able. It is dishonest at best, and deceptive at worst to advertise support for an update while the manufacturer knowingly creates and sells a version of the product that does not support the update.
I have seen numerous threads with owners of this card trying to update their firmware with the unsupported versions listed, which lead to system crashes and freezing, and I am making this post partly to inform them and others of this issue. The AMD post, and Gigabyte's website, should be edited to make it clear that only certain versions of the Gigabyte model listed are supported.