Energy-distance spectrograms of electron count rates displayed as a function of the distance along the Y_MSO axis. From top to bottom: MEA1 observations for MFB1, MFB2, and MFB3, and SES observations for M10 FB1. The vertical dashed green line delineates the CA. For each flyby, the spacecraft altitude (in Mercury radius) and the time (in UTC, HH:MM) are indicated below the corresponding plot. We note that the time increases from right to left. The red, green, and light and dark blue boxes above the corresponding plot delineate the SW, the magnetosheath, the magnetosphere, and the eclipse (or shadow regions) crossed by the spacecraft for each flyby, respectively.