There are 230mm cases with dates of 1896 and 1897, but these are very thin walled and were drawn from the older 100mm cases. If you examine them closely, you see that they are identical in every way to the original, even by weight. Usually they will have more modern dates stamped on the headstamp closer to the rim and in very small print. The cases in the photo do look different from those in my collection, perhaps they are later mfg. The older separate loading ammunition was used for target practice in the rebuilt guns. I have several photos that clearly show the older ammunition next to the modern gun. It doesn't make sense to me to practice with different ammunition than you would use in a tactical situation, but the evidence is that they did just that. There is still debate over when the original guns were rebuilt, some say 1905 or 1906 even 1908. I tend to think it was earlier but have not been able to verify this. The French came out with their gun in 1897, just one year after the Germans, but theirs had the recoil system. Why the Germans waited so long to rebuild theirs is a mystery. It is even possible that after the gun was rebuilt, they were using the older separate loading ammo and later rechambered it for fixed ammunition. The records are unclear.