This has led to the dispute being dubbed the “sick note strike”, although trade union RMT says poor management and a lack of overall staff is to blame.
Talks aimed at resolving a long-running row over driver-only trains on Southern Railway trains have broken up without reaching an agreement.
A commuter last night tweeted: “@SouthernRailUK How do we go about getting full refunds for the absolute shambles of a London to Brighton service you’re running tonight?”