Does Frank Herbert ever state who took over governorship of the planet Caladan after House Atreides departed for Arrakis? It seems to be implied that they gave Caladan up rather than governing both it and Arrakis. In contrast the Harkonnens govern Geidi Prime, their homeworld, and also governed Arrakis until the Emperor ordered the change.
I don't recall anything in the novel discussing what happened to Caladan after the Atreides departed. Was it mentioned in any of Herbert's sequels, or did he discuss it in interviews or leave notes?