The AQ catalog only says that this watch was "custom-made", which is not untrue... The Patents accorded to Mr Dubey and Mr Schaldenbrand in 1947, 1949 and 1952 (253,051, 260,791, and another one I can't find) mention that this mechanism may be adapted to many calibers. Nine additional parts are neede to adapt this mechanism to a Venus 188, and 13 to add it to a Valjoux or Landeron 48 (Source: Joel Pynson article).

Which is apparently what was done with the Heuer caliber offered by Antiquorum...

It may have been adapted by a private watchmaker, or even at the D&S shop. Who knows?

Did someone ask Cinette Robert herself (CEO of D&S)?? She is reputed for very good memory...