This was followed by the introduction of refurbished Class 230 trains on the route, which have seen teething problems with rolling stock technical issues and poor timekeeping.
Dilynwyd hyn gan gyflwyno trenau Dosbarth 230 wedi'u hadnewyddu ar y lein, gafodd drafferthion ar y cychwyn oherwydd problemau technegol gyda’r cerbydau a methu cadw amser.