Roedd Network Rail wedi rhoi blaenoriaeth i wella’r leiniau lliniaru yn 2016 yn dilyn addewid gan Chris Grayling i ddatblygu opsiynau ar gyfer y lein yn sgil y penderfyniad i beidio â thrydaneiddio’r lein i Abertawe yn 2017.  A hithau bellach yn 2020, dydyn ni byth wedi cael ymrwymiad i ariannu’r gwelliannau mawr eu hangen hyn.
The upgrade of the relief lines was identified as a priority by Network Rail in 2016, following a commitment by Chris Grayling to develop options for the line following the cancellation of electrification to Swansea in 2017.  Now in 2020, we still have no commitment to fund these much needed enhancements.