I am in Spain at present, and although I do have electronic copies of both British and French regaulations with me am a bit busy today, so do not have time to research this as well as I would otherwise wish to do.
From memory, the French 1791 Regulations and British 1792 Regulations had virtually identical methods of forming square from column and in both cases the regulations were for companies in three ranks doubling up to form a square in six ranks.
It is easier to consider this as rows, of either companies or double companies (the latter being French divisions or British grand divisions). The drill requires a minimm of 5 rows, two for the front face of the square, two for the rear face of the square and one to split in four quarters, two doubled up on each of the sides of the square. It does not matter how many "centre" rows there are, as long as there is at least one, nor does there have to be an even number of centre rows.
The British could theoretically perform this drill from their column of grand division, provided all ten companies were in the column. If the light company was detached, as it always was during Wellington's era, then British battalions needed to re-form into columns of company in order to use this drill. The British adopted 2 ranks as their norm, but continued to use this method to double these up into 4 rank squares.
The French were never able to use this method of doubling up into six rank faces of the square from columns of division since, even pre-1808, they did not have five complete rows of sub-units per battalion when in column of division. If they wanted to have six ranks in their squares they needed to do so from columns of companies, or from a composite column of two battlions. The French liked using columns of division, therefore used a modified form of the drill by which they no longer doubled up, so formed 3 rank squares. This enabled them to form squares from columns of division pre-1808 and continued to allow them to do so post-1808, provided all six companies were in the column. If the voltigeurs were detached they needed to re-form into a column of companies in order to use this drill (which is actually why Napoleon's 1808 Decree requires them to operate by company, not division, when either or both of the elite companies was detached.
Hope this makes sense.