PS4 - Supply crates cannot be looted anywhere in the world, therefore upgrade to level 6 settlement impossible. I am level 352, have finished the main quest and pacified England, have raided all monasteries and locations along rivers, as well as most of the civilian ones and garrisons. When looting the rectangular chests that were supposed to drop supply crates, I only get coin. Have been grinding for a while trying to find supply crates, as I need a last upgrade to get to settlement level 6....they are just unavailable. I found some suggestions that the glitch was caused by the Mastery challenges, which I, too, have started a while back. I can't pinpoint the exact moment supply crates stopped dropping, but I know for sure that they were available some time ago....thanks for thaking the time to read and look into it. There are a lot of people with this annoy8ng bug out here.