Derivation of age uncertainties. Black line shows average distance between all cluster members and an isochrone at a given age as measured on an HR diagram. Red horizontal lines show the average distance at our claimed age (solid line) and 1σ scatter of distances from the isochrone fitted by eye (dashed line). Age difference at which the average distance reaches the top dashed line is 1σ uncertainty for the age of each cluster. The calculated uncertainty is marked by an arrow. Note that such analysis is highly impacted by binaries and biases, so the described procedure is only reliable for positive age deviations.