Billy Mitchell is set to make a big mistake ahead of his wedding to Honey on EastEnders.

The couple revealed on Christmas Day that they had set a February 19 date for their wedding, with the nuptials likely to coincide with the soap’s 40th anniversary plans.

In new scenes airing next week, Billy excitedly plans the big day and announces his best man, also organising a disco and barbeque.

However, a dampener is put on his happiness after Honey realises that he has made a costly error.

What has he done?

Amid Billy’s financial difficulty, Phil secretly concocts a plan to get money and asks Mo to help in his scheme.

The soap’s 40th anniversary week will take place next month, and will give power to the audience, with fans able to decide the outcome of a love story.

Opening up recently about the celebratory plans, EastEnders executive producer Chris Clenshaw teased “explosive” storylines to Digital Spy and other press.

“Apart from the live episode, we’ve pretty much shot most of it and it’s looking brilliant. Expect everything,” he said.

Star Adam Woodyat added that anniversary week is “bonkers”, recalling: “I think I can safely say for all of us, we picked up the scripts and thought, ‘How the hell are we going to do this?’

“And we have. We obviously haven’t done the live element yet, we’ve done all the bits leading up to it, and it’s honestly brilliant.”