Why France would replace the Courbets before the Bretagnes

Which ageing French battleships would be replaced first in the 1930s, the Courbet or Bretagne classes?

The Courbets would go first, followed by the Bretagnes as the Dunkerque, Richelieu, and subsequent programmes supplied replacements.

The Courbets would be replaced before the Bretagnes. Two Courbets had already given way to the Dunkerque class in the French replacement programme before the Second World War. The remaining Courbets and one Bretagne were due to be replaced by Richelieu-class ships. The final two Bretagnes would then give way to whatever capital ships followed the Richelieus.