The Queen and the Duke of Edinburgh are set to move from Balmoral Castle to the Sandringham Estate in Norfolk in September.
A Buckingham Palace spokesperson said: "The Queen and the Duke of Edinburgh will depart Balmoral Castle during the week commencing 14 September to spend time privately on the Sandringham Estate.
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"Subject to the finalisation of the autumn programme, Her Majesty's intention is to return to Windsor Castle in October and to resume the use of Buckingham Palace for selected audiences and engagements. These plans will be kept under review and will of course be subject to all relevant guidance and advice."
Future arrangements for the 99-year-old duke are still being discussed.
It is not yet known whether Philip will remain on the Sandringham estate when the Queen returns to Windsor, or whether he will join the monarch at the Berkshire castle where they spent the lockdown.
The Queen's Sandringham estate in Norfolk
The 94-year-old monarch typically spends her winter break at her Sandringham estate, travelling up to Norfolk after the Christmas party for extended family members at Buckingham Palace in December.
The Queen usually remains at her private estate throughout the festive period before returning to London after the anniversary of her father King George VI's death on 6 February.
Since his retirement in August 2017, the Duke of Edinburgh mainly divides his time between Wood Farm on the Sandringham estate and Windsor Castle. Prince Philip had been staying in Norfolk before the coronavirus lockdown was imposed in March.
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Balmoral Castle in Scotland
The Queen and the Duke of Edinburgh have been residing at Balmoral Castle for their annual summer break since 4 August. The monarch and her husband took a private flight from Aberdeenshire from RAF Northolt in west London after residing at Windsor Castle for four months during lockdown.
The couple have been staying in Scotland with a minimal team of staff members, dubbed HMS Bubble.
Members of the royal family have visited the Queen and Prince Philip, including the Earl and Countess of Wessex, Princess Eugenie and her husband Jack Brooksbank and the Duke and Duchess of Cambridge.
The Queen's decision to spend a few weeks in Sandringham at the end of her summer break will come as a surprise to royal fans, as she and Prince Philip typically reside at Balmoral until the end of September or first week of October.
According to its website, guided tours of the grounds, exhibitions and ballroom at Balmoral will be available from Saturday 3 October.
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