Hi there, Andy! Welcome to planDisney.
I also live in the U.K., and I know that you can only buy a one-day ticket for EPCOT through the
My Disney Experience App when you are physically in the U.S. Once you arrive in Orlando, purchasing the ticket through the App is very easy. Simply log in to your My Disney Experience App, hit the + button and follow the Buy Tickets and Passes prompts. Since your planned visit on Monday is not during a major holiday, I expect there should be good availability for your visit.
EPCOT is my favourite and (in my humble opinion) the best Park across Walt Disney World. Not only does it host the fabulous
Guardians of the Galaxy: Cosmic Rewind, but where else can you sip and savour your way around the World (Showcase) in one afternoon?
What's even better is that your adventure will coincide with the ultimate
EPCOT International Flower & Garden Festival. I adore this celebration; EPCOT looks stunning, and the outdoor kitchens serve incredible delights. I'm so excited for you to experience it!
Andy, I hope this information helps today and that you enjoy a truly fabulous time at
EPCOT. We love to talk about Disney here, so please pop back anytime with any other questions.
Louise