public String getLastChangeTimeString(boolean useSource) {
		DataType dt = useSource ? sourceDt : refDt;
		if (canUpdate()) {
			return getDateString(dt.getLastChangeTime());
		}
		return "";
	}
Disassociates this DataTypeSyncInfo's data type from its source archive.
Ghidra/Features/Base/src/main/java/ghidra/app/plugin/core/datamgr/DataTypeSyncInfo.java