From June 1805 the second battalion of the Grenadiers and Chassuers had 6 companies each of 120 men, or 131 men including officers and NCOs, making peletons of 60men. Both battalions were combined to form a provisional regiment
First battalion had companies of 80 men so peletons of 40 men. both battalions formed a provisional regiment
The organisation does not appear to have changed to 4 companies per battalion till 15th April 1806, each then being of 120men. Their is a decree of 1st November 1805 for the guard infantry but it does not cover the organisation of the grenadiers per se, so potentially the organisation could have reverted back to the 29th July 1804 establishment of four companies of 80men per battalion on this date. The first decree specifically dealing with the organisation is as mentioned above 15th April 1806.
The organisation of the grenadiers a Pied and chasseurs is more complex than one might suppose.