This map shows the known location of corps on each side.
There are four corps per side, and obviously the location of most are not known to the enemy
The French are thinly spread along the river Elbe. They hold the town of Dominz to the north and the city of Magdeburg to the south. Their cavalry patrol the area around both locations, but there is a large area which is not covered.
The French reserves are known to be in the general area of Hanover, and Prussian agents have reported that large bodies of infantry are already marching east towards the river Elbe.
Prussian cavalry have secured the bridge at Parey and have been joined by the remainder of the corps. The French are aware of this, and cavalry from Magdeburg have arrived at Colbitz to contain the enemy cavalry.
The civilian authorities of both Stendel and Werben have advised Marshal Davout that all bridges over the river Elbe have been closed by enemy cavalry. They also report sightings of large Prussian columns moving towards the river.
By nightfall it is clear that the Prussians will reach the river line before sufficient French reinforcements can arrive to secure all of the bridges.