Bear with me if this question sounds dumb, I don't understand relativistic redshift and general relativity very well. To imagine it, I picture the universe as being on the surface of an expanding bubble. Now suppose a light ray was emitted during the big bang and hasn't reached us yet (because of the faster than light inflation immediately after the big bang). Shouldn't the amount of redshift then depend on how far away the source of light came from on this 'bubble'?

So the amount of redshift predicts the distance the position of the source of light emitted during the big bang. As the universe expands slower than light, light from increasingly further distance will reach us as time progresses. Eventually, we should get to a point where light from the other end of the bubble reaches us. After this point, light from a source that has already arrived will begin to return again.

Is this an accurate description of redshift? If so, how does it tell us the amount by which the universe has expanded? It seems completely arbitrary since we don't know the distance to the source of the CMB.