Could France count on a British battlecruiser against German raiders?

Why did French planning assume British battlecruiser support when Hood, Renown, or Repulse might not be available?

Their allocation was primarily a Royal Navy problem, and France could reasonably expect at least one British battlecruiser to support an allied response.

Battlecruiser allocation was a problem for the much larger Royal Navy rather than a reason for France to duplicate every British capability. Hood's flagship duties might constrain her movements during part of the year. Renown and Repulse provided two further fast-capital-ship options. France could therefore reasonably expect at least one British battlecruiser to be available for a coalition response when needed.