Drop
I guess you didnt read the above post about how many times that brass has been loaded.
As far as how many firings before the problem shows up……sounds like the brass is getting work hardened. The more its worked (fired and resized) and the harder the load (pressure) , the more “elasticity is lost.
You said how many times your customer's brass had been loaded. And then you also mentioned using a different brand of brass. You didn't provide YOUR experience.
