The group will tend to stagger itself on the return leg anyway as some people want to get straight home, some want to drink, eat and check out the area.
We have had this sort of thing before, usually we just pile(respectfully) into the carriage and see what happens.
If the conductor doesn't want to let fully assembled bikes on the train I will personally drop the wheels out of peoples bikes whereupon they become luggage and not bicycles.
Then I will reassemble them when we get back to London.
We should definitely be able to get back OK though.
There's also the Viking Trail along the sea wall to Margate for more train options plus Canterbury is about 6 miles away.
There's also the Viking Trail along the sea wall to Margate for more train options plus Canterbury is about 6 miles away.