I am sure that creation scientists have written papers supporting their positions on virtually everything, but whether or not that includes the speed of light not being constant or not I have no idea - that was something I threw out, not something I had read. I personally believe that God created the universe in a mature state (just as He created Adam in a mature state and the Earth in a mature state), which would not require any variability in the speed of light.
I suggest you read some of their literature or at least visit the Creation Research Institute and related websites to get an insight into some of their views and links to their works. I have not read very deeply into their scientific views because most of it is above my head. I do know that they have published many papers in quite a number of scientific fields.