The work will affect trains from around 11pm tonight (January 2).
Engineering work is taking place overnight between South Croydon and Oxted, closing some lines.
As a result, the 11.07pm train from London Bridge to Uckfield service will terminate at East Croydon.
A replacement bus will run from East Croydon to Uckfield, calling at all stops.
The 11.20pm train from London Victoria to Oxted service will terminate at East Croydon.
A replacement bus will run from East Croydon to Oxted, calling at all stops.
