Did Light Move Faster In The Past?

I've been asked this question by Creationists for some reason, and recently seen it on a forum. Here is my reply.

The universe is expanding - space itself is expanding. What does that mean? Every object is moving away from every other object. I guess it's kind of like everything in the universe is shrinking relative to the universe as a whole. Thus distances between things are constantly increasing.

Suppose light travels from point A to point B in time T. The speed of light would be equivalent to

c = (B-A)/T

Now suppose that after the light travelled, the space it had travelled expanded. B-A, the distance between the two points, increases.

Thus we could say the light travelled from point A to point B faster than the speed of light; however when it did it, it travelled shorter distance at the speed of light rather than the same distance faster than the speed of light.

I suppose one could say that the speed of light used to be greater and will be less in the future in Universe units, but then you'd also have to agree everything is shrinking.

Instead of describing it this way (which may not be 100% correct anyway) we describe it as space expanding and distances increasing - and a constant speed of light.

For the Young Earth Creationists who think this supports their position somehow, this "change in the speed of light" happens at a predictable rate, which scientists account for.