See where it says “Trigger value”? Right next to that it says “Release value.” The trigger value is what causes the action to happen. The release value is what turns off that action.
For example, if one of your cells gets to 4.21v (4210mV, your “Trigger value” for “Cell over voltage”) then the BMS will stop the charging. It will stay stopped until that cell drops below the “Release value.”
Notice in my settings where it says “Overvoltage” and “Overvoltage release”?