Ancient chinese dating system
Chinese is a highly monosyllabic language and so the opportunity of using rebus writing would have presented itself extremely frequently.
The earliest form of Chinese writing is called the oracle bone script, used from 1500 to 1000 BCE.
Perhaps it already had when these symbols were incised into the pottery, which could mean that these artifacts have writing on them, but there is no way to prove one way or another.
At best we can say is that the symbols were precursors to Chinese writing.
In other words, the symbols acquired linguistic values and became logograms.
However, exactly when this switch happened is unknown.