I am currently working on the etat nominif for the 57e Ligne. The regiment seems to be missing a few officers before the battle with only 66 officers out of a full complement of 69 spots. I understand that the depot would send the batallions du guerre extra officers prior to the start of the compaigne to make up for losses down the road. However, what is written on paper for the rolls and some officers' promotion dates do not seem to add up. Would officers still command in the role of a Lieut. even if they were promoted to Captain? I am missing the etat nominatif for April and May, which would make this process much easier. As you can see below, the regiment has many vacant spots for Lieut. in March 1809. I know of two officers who came from the 4e Bat. and were wounded at the battle.
For example, 3e Voltigeurs Lieut. Pierre Pontier was promoted Capit. on 20 February 1809, but on the reports for 1 February and 1 Mars he is still shown as a Lieut and his replacemet Lieut. Basset was not promoted until 22 August 1809. The commanding officer of the 3e Voltigeurs was Capit. Bernard Boyer and he was not promoted until 1813. The 2YB646 does not give the actual date when the list was recorded, but only the year. So any changes during that year are recorded. The 1805-1807 records are almost impossible to read, with so many men being killed, wounded, or promoted and the scratching out of theirs names. Some positions have seven or eight different names!