Two organisers of Disability Pride were late for a committee meeting in Hove after they were unable to board a train from Seaford.
Founder of the Pride event Jenny Skelton of Saltdean was with disabled committee member Sammy Taylor, who was unable to board a train on Monday (November 6) because there were no staff on board to set up the wheelchair ramp.
Govia Thameslink, which operates the Southern franchise has apologised to the passengers, and said accessibility is a 'high priority'.
The incident follows the introduction of driver-only operated trains, with on-board supervisors replacing conductors, which has seen the RMT and ASLEF unions stage strikes over the last 18 months.
Ms Skelton posted a Facebook status which said: “Oh, the brilliantly beautiful irony. I am on my way to chair a meeting of Disability Pride Brighton which is all about disability discrimination and raising disability awareness but I am going to be late.
“I will be late because Sammy Taylor and I are stuck at Seaford Station. Even though we arrived 15 minutes early for the train to Brighton, Sam is not allowed to get on it because there is no one to help the train driver with the wheelchair ramp.”
On its website, Southern advises disabled passengers to book assistance at railway stations 24 hours in advance. At staffed stations, it advises passengers requiring assistance to arrive 20 minutes early.
But Mr Taylor, who lives in Seaford but regularly travels to Brighton, said: "I do not know when I want to travel all the time, you have got to give them a time. I can't always say what time I want to come home."
Ms Skelton added that although she and a friend had offered to help with the ramp, they were ‘not permitted to touch Southern Rail’s property’, and that although Southern had offered to provide a taxi, it would only use one from Brighton, despite the fact there was a wheelchair accessible taxi in Seaford.
This meant the pair has to wait for the next train 30 minutes later, which had a member of staff on board to operate the ramp, but they were late for their meeting.
A spokesperson for Southern said: "Making our train services accessible to everybody is a high priority, and we apologise to Mr Taylor and Ms Skelton.
"We have set up tried and tested procedures for the rare occasions that passengers need travel assistance at unstaffed stations on trains running without on-board supervisors, but it appears these were not flexible enough in this instance.
"If the train had been assigned a conductor rather than an on-board supervisor – as the RMT is demanding – it would have had to be cancelled.”
Emily Yates of the Association of British Commuters said: “Unfortunately, the deterioration of disabled access on Southern is so bad that it no longer surprises me to hear of an incident like this. We hear of incidents every week, and these are just the people who contact our campaign to report them.
“GTR has removed the guarantee of a member of staff on this very rural network, even adjusting their disabled people’s protection policy to ask for 24 hours notice when travelling from unstaffed stations. Since the vast majority of stations on Southern Rail are unstaffed or partly staffed, this means an end to spontaneous travel for many disabled people.
“The situation is a disgrace. After campaigning on the issue for a year we have become completely disillusioned with the platitudes from the Department for Transport and the Office for Rail and Road; who have knowingly stood by and approved this as part of their proxy dispute against the RMT union.”