As commented everything disappeared and some companies would not even take backorders. Brass is reloaded several times over so it is the easiest item to get by on. I suggest you focus on a few types of powders and primers. Don’t wait until a panic and do what a friend did. He backordered a lot of primers from different companies and forgot who had had orders with. When the panic ended and the companies started filling their backorders he ended up with over 100,000 primers plus a lot of powder he had backordered. I told him that if his house ever catches fire the Fire Department will need to evacuate the entire block and watch the explosions.