The Duke and Duchess of Cambridge have moved back to Kensington Palace to prepare for the imminent birth of their new baby, MailOnline can reveal today. The couple, whose second child is due on Saturday, returned to their London base, just a few minutes’ drive from the private Lindo Wing at St Mary’s, Paddington, on Sunday night after spending the weekend at Kate’s family home in Berkshire, where they took a trip to their local farm park. The news came as Kensington Palace revealed William will enjoy what amounts to six weeks’ paternity leave around the arrival of the new little prince or princess. Scroll down for video . Reunited: Prince William, pictured with his wife last month, has finished his air ambulance pilot training early so he is guaranteed to be with the Duchess of Cambridge when she goes into labour . Change: Until today the second in line to the throne, who is a trainee pilot with the East Anglia Air Ambulance in Norfolk, had been expected to still be working around the time his wife is expecting their new baby. A royal spokesman announced that the second in line to the throne had completed his latest stage of his training as a pilot with East Anglia Air Ambulance (EAAA) ‘earlier than expected’ - and would not be required to embark on the final stage until June 1. The future king had already announced that he planned to take two weeks’ statutory paternity leave after the birth. With his enforced absence from work happily coinciding with the birth of his second child, William will now take the next month and a half off as unpaid leave, aides said, with immediate effect. Good timing? Prince Harry, pictured in Australia, also announced today that he will be back in the UK to watch the London Marathon on Sunday, meaning he may also get to meet his future niece or nephew . The palace also announced that Prince Harry, who is currently on deployment with the Australian Army, will briefly return to the UK this weekend to present the winners’ medals at Sunday’s London Marathon and, if all goes to plan, meet his new niece or nephew. Harry – who is soon to drop down a place in the line of succession to fifth – is already travelling over to attend the Gallipoli Campaign centenary commemorations with his father, Prince Charles, on Thursday. The prince, who is patron of the London Marathon Charitable Trust, will return to Australia on Monday to continue his placement. The Mail understands that in recent days the Duchess, who carried out her last public engagement in March, has been taking her mind off the impending birth by spending a few days with her parents, Michael and Carole Middleton, at their sprawling Georgian mansion in Bucklebury, Berkshire. On Sunday she and Carole took her eldest son, Prince George, for a visit to nearby Bucklebury Farm Park where youngsters can meet a variety of animals from lambs to wild boar and enjoy a large outdoor playground. The little prince is a frequent visitor to the park with both his mother, nanny and grandmother. Kate appeared unbothered by her pregnancy, according to onlookers, as she carried and cuddled George, accompanied by a low-key Scotland Yard security detail. The family returned to London on Sunday night to make last minute preparations for the latest addition to their family, who will become fourth in line to the throne. In a statement today a Kensington Palace spokesman confirmed that William, who is employed by a private company, Bond Air Services, while working for the EAAA, had sailed through his initial training so quickly that he would now be able to be with his wife both before and after the birth. Plans: Kate plans deliver her child at the Lindo Wing, where the cost of giving birth naturally is up to £10,000, and where their son George was July 2013 . They said: ‘The Duke of Cambridge has completed the first phase of his in-work air ambulance helicopter pilot training with Bond Air Services earlier than anticipated. ‘This is due to a combination of The Duke performing well in the various modules and having very good flying conditions that allowed flight training and assessment to progress more quickly than had been planned.’ The Duke was the first member of the Royal Family to take advantage of statutory paternity leave, which was introduced in the UK in 2003. After the birth of his son George he took two weeks off while working on Anglesey. With his second child due on Saturday William will now be off work until June 1, although it will be unpaid, Palace sources say. Government rules state fathers are  paid £139.58-a-week for a maximum of two weeks. It is understood the Prince will not claim it. Fathers are entitled to two weeks paid paternity leave and up to 26 weeks’ additional paid leave if the child’s mother returns to work. The spokesman explained that given the lengthy gap between now and the final stage of his training, the prince has been on unpaid leave since Friday. He will undertake a handful of public engagements in late May, likely to include joining his grandmother, the Queen, at a Buckingham Palace garden party, before recommencing his training at the start of the following month. His spokesman added: ‘His final block of in-work training requires an uninterrupted three week block of working time and the availability of the new EC145 helicopter that will be used for missions. This has always been scheduled to commence on 1st June, following a pre-planned period of official royal engagements in late May, details of which will be announced in due course. ‘As he now will not have any further training to complete after returning from paternity leave, he will not return to duties with Bond until that time, and will remain on unpaid leave until then.’ While it is unlikely the new little prince or princess will become monarch, it is not unheard of. The Queen’s own father became George VI after the abdication of his elder brother, Edward VIII, over his love for American divorcee Wallis Simpson. The current monarch celebrated her 89th birthday quietly with her husband, Prince Philip, at Windsor Castle where she is holding Easter Court. Not only has she now entered her 90th remarkable year, but the Queen will soon also become the longest reigning monarch in British history.
Prince William had been expected to work as pilot until the end of April . Duchess of Cambridge is based in London and baby is due this Saturday . William using unpaid leave and paternity leave to stay off work until June 1 . Prince Harry is back for marathon on Sunday so could see niece or nephew .