Leon stood on the edges of the French and Luxembourgish Border. Frankly speaking, the German troops in the Grand Duchy had been focusing more on building defenses around the capital, which was the most strategically important region of the minor and neutral European nation.
While this gave the French time to rearm, and resupply, as well as tend to the wounded. Few reinforcements were provided to them. With the losses sustained currently, and their focus being primarily on invading Belgium, what with Luxembourg already being a lost cause.
The French Republic only gave Leon a few brigades worth of men to replenish his losses, but no more than that. His orders hold the line no matter what the cost. Once victory in Belgium had been achieved, 250,000 men would be sent to aid him.