In my recent game, I researched far ahead of my era progress in my game. This meant that I was able to research the tech that unlocked railroad stations while still being in the early modern era.

After building two railroad stations while still being in the early modern era, these two stations did not update graphically with a rail line, and did not offer movement bonuses to units moving between the two stations. 

When I advanced to the industrial era, I was required to build a 3rd separate railway station to see a functional rail connection to my first rail stations, however, the initial two rail stations that I built in the early modern era were still left disconnected from each other.

I assume this is a bug, as the rail tech and buildings purportedly offer the movement benefits without any required era.  

To Reproduce: 1 Enter Early modern era, 2 Research train tech and Build two train stations, 3 Observe, 4 Enter industrial era, 5 Build another rail station