Complex sentence: The original stations on that line included one named "Llantrissant for Cowbridge"; this was simplified to "Llantrissant", by which time the SWR had amalgamated with the Great Western Railway (GWR) in 1863.
Split into simpler sentences: The original stations on that line included one named "Llantrissant for Cowbridge". The station name was simplified to "Llantrissant", by which time the SWR had amalgamated with the Great Western Railway (GWR) in 1863.