A bizarre new rule means Pippa Middleton's wedding guests may be in for a big shock.

Do you have plans on May 20?

Oh, it’s Great Aunt Mildred’s 93rd birthday? You better call and tell her you can no longer make it because we’re all flying to England to attend Pippa Middleton’s wedding.

That’s right, we’re all invited to the most anticipated almost-royal wedding of the year.

Well, sort of.

According to UK's Telegraph, the Church of England - which runs the Berkshire church where Pippa Middleton and fiancé James Matthews are set to wed - recently released new guidelines on "celebrity weddings", which states that regular folk should have the right to attend.

The document, entitled Celebrity Marriages in Anglican Cathedrals and Churches, states that "a marriage is a public ceremony which at the least all parishioners are entitled to attend".

That means that all residents of the parish surrounding St Mark's Church theoretically have the right to rub shoulders with the Duchess and Duke of Cambridge, as well as Prince Harry and Meghan Markle, to watch Pippa tie the knot.

(Alright, so technically not just anyone can attend...It just means we'll have to fly over a week or two earlier to establish ourselves in the area and go to a few church services first. Easy.)

LISTEN: Why Meghan Markle is the Princess we all need.

The document also says that regular folk can only attend "as long as there is available seating or standing room unless a genuine question of safety or security arises".

So...should we camp out the night before, or...?

Thankfully, Pippa's reception is being held on a private estate, so the same rules don't apply.