in the past I've signed up for notification on a certain bullet at shooters pro shop . I did get notified when it was back in stock . I was fast enough a few times , other times I was too slow and they were sold out again .
The good thing about shortages is that it forces you to explore options that you ordinarily wouldn't have. I've discovered many good bullets and powders that I now use because my regular components just weren't available. Now that I've developed new loads, I won't be going back to the old ones.