My take on ringing is that if you're in a grade by virtue of recent performance equivalent to the next season, then that's yours by right. Just having a bad season and dropping down, then going back to form, isn't the same thing.
With an apparent arbitrary cut off between grades there will always be those that sit either side of it.
Ultimately B & C grades are the easiest grades to grab silver in, because AA probably demands you are in the top 3 of the day, and AA is full of people who on any given day you wouldn't rule out of being in the top 3. A is full of people that have either fallen out of AA, or because they're on their way up, so the A scores at the top are normally high as well.
If you're a new shooter i've got no issue with grabbing it as you climb % because when you get to the top you can starve before you see any more and if that's your motivation (and there's nothing wrong with that) then crack on.
BFTA/NSRA County Coach
CSFTA Chairman/BFTA Rep