Hi Amy and welcome to the Disney Parks Moms Panel.
It's always lovely to be able to answer a question from a fellow Brit!
The answer to your question really depends on who you book your holiday with and what their terms and conditions are. To be absolutely sure, you would need to check this with the Travel Agent / Company you intend to make your booking with, prior to going ahead.
I can tell you that historically, free dining promotions have been released in the month of April for stays (on select dates) at the Walt Disney World Resort during the following year, for UK Guests.
If you are currently considering booking a 2017 holiday to the Walt Disney World Resort and adding a Disney Dining Plan to your package, I would highly recommend that you wait for another couple of weeks to see if a free dining promotion is released.
Be sure to keep a close eye on the
Deals section of the Walt Disney World website.
Wishing you a magical holiday filled with memories which will last a lifetime!
Emma