Very slow intersteller travel

I am confident that there are some interstellar asteroids, comets and even Earth size planets; perhaps only one or two per century, but we will not be prepared for the next flyby unless we start soon. We can put two female humans in an asteroid that passes closer than Earth's moon about once per year. We would send them with lots of supplies and a sperm bank and an embyo bank. We should launch supply craft in random directions before the first colonists leaves Earth. That way it would be probable that supplies could be delivered to each habitat at least once per decade. Soon most of the habitats would have about a century of basic needs. Most items would keep long term in the vacuum of space at about - 200 degrees f. The habitat dwellers would want things not in the supplies so they would be motivated to find ways to produce these items
When the children born in space reached teen age, they would want their own habitat and that would be easy when a vacant asteroid or comet passed close by at low speed relative to the parent asteroid. In 1000 years there could be more than 1000 habitats in asteroids and comets, a few of them hyperbolic and heading into the Oort cloud even if only a few originated from Earth. The habitats would communicate with each other and Earth daily or oftener on forums such as www.able2know.com www.space.com
Technology advances would likely allow the supply craft to chase the habitats up to a few light years from Earth before the supplies would be too stale to be usable. Habitats that had not achieved self sufficiency would die out, but my guess is some would make it to a new solar system in less than a million years and about 40,000 generations perhaps long after all intelligent life on Earth is extint. Then a new Adam and Eve would land on Earth from one of the orbiting habitats, to multiply and replenish the Earth. Neil