I did also think that that sounded quite low, but if they are thinking of pulling a large number of international tourists, these will probably be coming from places that are directly connected to Bedford and Wixams railways stations, such as London St Pancras, Luton Airport Parkway and Gatwick Airport. These two stations are also along the Midland Main Line, which provides direct connections to large swathes of the East Midlands and places as far north as Sheffield.
There is also one piece of the puzzle that I feel would make public transport a far more feasible option for a greater amount of the country, and that is if Universal were to provide some sort of connection from Milton Keynes Central train station, which is relatively close. Now that might not sound very important, but it does open up quite a large opportunity because Milton Keynes Central lies along the West Coast Main Line. This would open up a direct train route to the park from the West Midlands, the North West of England and all the way up into Scotland. It would also connect the park directly to a massive interchange hub in Birmingham New Street, which would make the train journey easier for many more people (myself included!).
If I were local (sadly, I’m not), I’d be really interested to hear about whether Universal have considered connecting to Milton Keynes in some way to further reduce the strain on the roads.