Queen Elizabeth
Britain to mark Queen Elizabeth II's 65 years on the throne. In this photo, Britain's Queen Elizabeth leaves after attending the Christmas Day service at church in Sandringham, eastern England, Dec. 25, 2015. Reuters/Peter Nicholls/File Photo

The news that Queen Elizabeth II was missing Christmas church service for the first time in nearly 30 years sparked much concern over the health of the 90-year-old British monarch. But while the effects of her “heavy cold” awoke many to the mortality of the only ruler most Britains have ever known, the leading institutions in the United Kingdom will not be caught off guard by her death.

Preparations have already been made for what will happen in the event of her death, which is understandable given that it is likely to be the biggest event in recent British history as well as one of huge global significance. The Queen has sat on the throne since the death of King George VI in 1952, meaning her death would be the first of a British monarch in the new technological age with television and social media amplifying the coverage and the significance of her passing.

The funeral would undoubtedly be the biggest Britain has witnessed. The Queen’s body will lie in state at Westminster Hall, as was the case when the Queen Mother passed away in 2002. On that occasion, an estimated 200,000 members of the public visited to pay their last respects. Many more will likely leave flowers outside Buckingham Palace, as they did when Princess Diana died in 1997 when an estimated one million bouquets were left.

The funeral itself would likely take place 12 days after the Queen’s death. The coffin will be transported to Westminster Abbey via gun carriage along a meticulously planned route. When Diana died, officials were caught off guard by the scale of the response and as a result made a late alteration to the route of the funeral procession to accommodate the huge crowds.

Likely determined to avoid a similar occurrence, while it may sound morbid to some, plans for the funeral are regularly updated, with the Queen consulted. Indeed, the wedding in 2011 of the Duke and Duchess of Cambridge was also used as a dress rehearsal for the route the Queen’s coffin would take, according to a royal aide spoken to by Britain’s the Daily Express at the time.

"Obviously we all hope such a sad event will be a long way off - yet we need to rehearse the logistics and timings for what will be a huge ceremony," the aide said.

"The Queen, who is very pragmatic about this sort of thing, knows about the dry run. The arrangements are reviewed annually and any significant changes have to be approved by her. There's no sentimentality involved on her part; she actually takes rather a keen interest in the details."

Those are not the only plans being made. The state broadcaster the BBC also conducts rehearsals for how it will deal with the Queens’s death. Those plans were leaked in unfortunate circumstances last year when a BBC Urdu reporter, not realizing what she had seen was a rehearsal, tweeted that the Queen had died.