Here in the Netherlands, we have an e-tailer called Azerty, one of the bigger names. Prior to the 6800 (XT) AIB release today, they have released a statement about availability. And their words are quite worrying.

Azerty reports the following statement (this is translated fro Dutch):

Unfortunately, many manufacturers are not yet clear about the specifications and prices of these video cards, and all cards have an unknown delivery time. As soon as information about new models is available, we will post them on our site.

We know that there is a lot of demand for RX 6800 (XT) video cards. Supply is very scarce and delivery times are unknown. It is therefore not useful to contact our customer support center for more information; unfortunately we do not know more than we indicate here. As soon as there is really concrete information about delivery times and availability, we can share this, but at the moment there is no news.

We are hearing signals in the market that the delivery problems of these cards could last for many months, well into 2021. We therefore advise our customers to take into account delivery times of RX 6800 (XT) video cards of several months.

Next to this news item, I did some rounds, and from the looks of things, availability is unbelievably low, if available at all. EU price search engines show this:

And this one is also interesting: 

Dutch e-tailer expects Radeon RX 6800 (XT) availability issues far into 2021