It’s a nightmare. In Belgium (getting home from ssec) and southern England they have sold 8 tickets to guys with bikes and then only allowed three bikes on at a time, if there were not any bikes ready on the train.
Every f***ing time we have had to negotiate and sometimes it’s been a case of “gotta get off at the next station, there are too many if you” and then I explain that we will take the wheels off and I will be one guy with ten wheels and you have a bunch of guys with frames and no one here has a bike.
Also blocking strategies to make sure you are first on before other cyclists helps.
It’s a lottery where you need to fight.