The departure had been fixed for the second week of June. Bouillé still hoped for a movement among the imperialists, and he requested a delay. On the 16th he was informed that the royal family would start at midnight on the 20th. He had sent one of his colonels, the Duke de Choiseul, to Paris for the last instructions. Choiseul's horses were to fetch the king at Varennes, and he was to entertain him in his house at Montmédy. He had the command of the farthest detachment of cavalry on the road from Montmédy to Châlons, and it was his duty to close up behind the royal carriage, to prevent pursuit, and to gather all the detachments on the road, as the king passed along. He would have arrived at the journey's end with at least 400 men. His last orders were to convey the king across the frontier, if Bouillé should fall. The great abbey of Orval was only a few miles away, and it was thought that, at the last moment, it might be found safer than the hostile soil of France.
Choiseul was not equal to the difficult part he had to perform. He set out for his post on the Monday afternoon, carrying with him a marshal's baton, which had belonged to his uncle, and the queen's hairdresser, Léonard. For Thursday was the solemn festival of Corpus Christi, when a military mass would be celebrated in the camp, and, in the presence of the assembled army, Bouillé was to be made a marshal of France. The queen could not be allowed to appear at such a function without the artist's help, and he was hurried away, much against his will, without a word of explanation. The king's sister learned the same day what was before her. There had been an idea of sending her on with the children, or with the Countess of Provence. The Princess, who was eminently good, and not always gracious, did not enjoy the confidence of the queen. She was one of those who regarded concession as surrender of principle, and in the rift between the Princes and Marie Antoinette she was not on the side of compromise. Provence came to supper, and the brothers met for the last time. That night their ways parted, leading the one to the guillotine, and the other to the throne which had been raised by Napoleon above every throne on earth. The Count and Countess of Provence both started at the same time as the rest, and reached Belgium in safety.