How is it that the point at which the effective receding speed of galaxies approaches C and the origin of the oldest light to reach us possible is the same? I mean, the big bang occurred about 13.7 BY ago so in an expanding universe (with an inflation period with effective receding speeds exceeding C) the oldest light we would be able to see would be light that originated from a source 13.7 BLY away. But I don't see a reason why that source would also coincidentally be receding at C?
Let's say for a moment that the universe is 100 BY old. In such a universe the farthest sources of light we would be able to detect would also be at the point where the effective receding speed reaches C, no? We would not be able to see farther, because the light would be red shifted into oblivion due to expansion, no? Similarly in a way to a light source that is approaching an event horizon. The closer it gets, the more red shifted it is until it is beyond the possibility of detection at the border of the event horizon.
Why do these two restrictions line up? Are they dependant on each other in some way, or did I simply make a mistake?