Good evening,
My great gran would have travelled from Oxford to London to train as a domestic servant in a Stamford Hill convent, then by the 1911 census she was working as a servant in Bexhill in Sussex. I guess she got the London to Brighton line but got a train that turned off at Keymer towards Bexhill when she travelled down to Bexhill to start her new job. By about 1916 she was in Rochford, Essex.
She would have 4 choices of route;
London to Hastings via Wivelsfield (Burgess Hill), Lewes, Polegate and on to Bexhill. This may have required a train change.
London to Hastings via Hurst Green, East Grinstead and Lewes etc.
London to Hastings via Hurst Green, Ashurst, Rotherfield, Mayfield, Heathfield, Hailsham and onto the coast line. This may have required going into Eastbourne to change trains.
The 4th route was further east, Tunbridge, Tonbridge Wells, Robertsbridge, Battle and to Bexhill but at the other station.
All of those could have involved changing trains at that time although I think the first one always had a through train. My brother was the expert on trains in the south east but no longer with us.
John915