  We report a temperature dependent x-ray diffraction study of the electronic
ordering instabilities in the kagome material CsV$_3$Sb$_5$. Our measurements
between 10 K and 120 K reveal an unexpected reorganization of the
three-dimensional electronic order in the bulk of CsV$_3$Sb$_5$: At 10 K, a
2x2x2 superstructure modulation due to electronic order is observed, which upon
warming changes to a 2x2x4 superstructure at 60 K. The electronic order-order
transition discovered here involves a change in the stacking of electronically
ordered V$_3$Sb$_5$-layers and agrees perfectly with anomalies previously
observed in magneto-transport measurements. This implies that the temperature
dependent three-dimensional electronic order plays a decisive role for
transport properties, which are related to the Berry-curvature of the V-bands.
Our data also show that the bulk electronic order in CsV$_3$Sb$_5$ breaks the
6-fold rotational symmetry of the underlying $P6/mmm$ lattice structure.
