"A new life awaits you in the Off-world colonies. The chance to begin again in a golden land of opportunity and adventure."
By late 2019, the Dominguez and Shimata colonies had been settled and humans on Earth were encouraged to emigrate to the colonies; this was promoted aggressively with advertising from the Shimago-Dominguez Corporation extolling the adventure and opportunities awaiting them if they left Earth, as well as promises of financial and personal incentives; for example, all colonists were promised a free replicant for their personal use.
Behind the scenes
The actual conditions on these colonies are never shown in the films, but the setting hints that the situation Off-world is not as rosy as the advertisements claim. The replicants are designed to survive dangerous harsh labor and environments. Roy was designed specifically for use as a soldier, recalling the battles he fought Off-world, and it appears that Leon and Zhora also had considerable combat training. Zhora was described as having been a member of a kick-murder-squad. Finally, there is the intensity of the marketing campaign itself; although the Los Angeles of 2019 is a miserable dystopia, its population still apparently requires aggressive promotion and considerable financial incentives to leave for these supposed paradises.
A deleted scene notes that Rick Deckard's ex-wife left him for a man Off-world. A draft of the script dated February 23, 1981 also mentions the Dominguez-Shimata Colony. The novelization mentions Dominguez and Shimata as separate colonies.