Does the colony have a roof over it? If not then you should get one. If the colony is otherwise predator proof then once you get the roof then you can get rid of the cages and let them build there own warren.
Just thought I'd share some stuff that I have found that maybe helpful to new Breeders:
1. Breeding and Genetics- The most you want of Flemish Giant blood in your rabbits is 25% as it will affect your Meat to Bone Ratios. The main things that a meat breeder should breed for are motherly...
If you worry yourself about whether you will be able to kill them or not you will end up not being able to do it. However if you are desperate, hungry, need the rabbit killed and think of the burden it is financially you should be able to.
Standard Rex are the best as you get fur and meat. But if you focus to much on meat quality you lose fur quality. Followed by the Flemish Giant who is better for slow grow out of a long period of time (20-30 weeks) then butchering for fur quality. The only difference if grown out to this age is...