Ann: Entitlement Issue Results, page-118

It will be interesting to see how this plays out.
Obviously, Codelco denies these rumours but, it has in fact, reduced production already since June & with their smelter undergoing major maintenance in November these rumours could have some truth behind them. Perhaps likely to be in excess of 10% but 50% seems illogical.
Already at 7.92% reduction year on year to Sept.
https://www.mining.com/web/codelco-profits-slump-50-to-september-cuts-production-target/

In June Codelco forecast Cu production at 1.61m tonnes but then revised down to 1.49-1.51m tonnes in August only to announce 1.435-1.465m tonnes in October. Seems they better hope the smelter shutdown goes without any hitches.