Princess Kate has rarely deviated from her favorite tiara since marrying Prince William in 2011. Even though royal watchers hoped to see a new-to-her design come out of the royal vaults, the Princess of Wales returned to Queen Mary’s Lover’s Knot Tiara at the Omani state banquet —and there could be a very sensible reason why.

The Royal Family welcomed the sultan of Oman, Haitham bin Tariq Al Said, for an official visit to Britain on October 20—the first time an Omani ruler has visited the U.K. in 44 years. Following a day of welcome events at Windsor Castle , King Charles hosted a glamorous state banquet, with Kate wearing a new Elie Saab gown and her go-to tiara.

While a number of comments on social media lamented the fact that Princess Kate was wearing the Lover’s Knot Tiara yet again, former royal butler Grant Harrold says that there’s likely multiple factors at play.…