Same as Figs. 7 and 8 following up 15 and 5 min pre-merger alerts, but using the updated sky-localization obtained 1 min before the merger. For this scenario, only events detected 15 min or 5 min before the merger with sky-localization less than 1000 deg² are considered. The expected number of VHE possible detections includes the CTA visibility because LST and MST antennas are not able to observe below the elevation angle of 30° (zenith higher than 60°). The plots in the right column show the LST array and the plots in the left column the MST array.