This snippet is pre-Regency but I think it deserves a mention.
In May 1762 King George III and Queen Charlotte moved into Buckingham House, which was called Queen's House.
In 1800 Wyatt built a new grand staircase with a central and two branching flights....Although the palace was being gradually adapated for ceremonial use, Queen Charlotte continued to find nostalgic pleasures around her. The royal 'Bookbinders Shop' was there and in the Queen's Garden she had carnation stages, and evergreens as in earlier years. Her elephant and zebra were gone, but the King's flocks and herds remained, and the patoral scene, enlivened in due season by haymaking and harbvesting of crops from plantations of fruit trees, preserved unchallenged the tradition of the Duke of Bucking ham...
Queen Charlotte by Olwen Hedley.