There is exactly the same set up as what is going to happen at Forest Hill when I go to visit my parents in Epping which is at the end of the central line. It's an overground tube station, with a bridge, one side the gates are permanantly locked and the other side there are three barrier gates. There are even more commuters travelling home from the city in Epping and it is a nightmare getting over the bridge on your way home. It can sometimes take about 10 minutes just to reach the barriers - and with the stampede of people going over the bridge it often creates a bit of barging with the few people trying to get over from the otherside to get on the train.