(1956, David Knight, Josephine Griffin, Marie Lohr)

Promotional short in which an American tourist journeys by train from London Victoria to Sussex, where he joins the crowds going to Glyndebourne and learns about opera.
Views of Victoria Bus Station show London Transport RTLs leaving, while two RTs (one a roofbox variant) wait:

At Lewes railway station he finds well-dressed folk heading for two Southdown shuttle buses. Most clearly seen is the rear one, 1276 (HUF276), a Leyland Tiger PS1/1 delivered in 1948 with a Beadle half cab body but rebodied by Beadle with this full fronted design in 1954:
There's a glimpse of the fleet number of the front vehicle, which reveals it as similar 1277 (HUF277):

Smitten with a young lady in a blue coat, our hero follows her to Glyndebourne House by taxi!