Yes RD used a Lemania movement for the Monopusher reference in this case design (Much More). It is not the same 2310 base in their Hommage or Sympathie references but it is a Lemania caliber nonetheless. Hope that helps π
The original poster, Humanist has a watch with the first gen. RD Cal 57, which is a modified Lemania 8810 twin barrel caliber upgraded and brought up to Geneva Seal standards. Cheers, Tim