Yes, UK will be at the Potomac HG but I cant answer about their stock. Likely nobody knows yet, as availability is still small and its a long ways away yet.

I'd guess there is a good chance they'll at least have a couple, even if not in your size or a color you want. You'll at least get a chance to see them.

Also, dont be afraid to ask if the have one there personally. I always bring all my kilts with me for display, so people can see what they look like broken in.