EP240408a: GSP optical upper limit

Following the detection of the fast X-ray transient EP240408a by the Einstein Probe (Hu et al. GCN 36053), we initiated observations of the fast X-ray transient location starting on April 9 at 10:46 UT (~17 hours after the trigger) in the r band. These observations were conducted using the 1-meter telescope at the Las Cumbres Observatory node located at Siding Spring Observatory in Australia. We report that no new optical source was detected in the co-added images within the EP/WXT error box down to ~21.5 mag. These observations were taken as part of the Global Supernova Project.