The estimated date of 1815 for the trade card is accurate.
Edmund Smith first appeared at Maddox Street in the Land Tax assessment book for 1814.
Princess Charlotte of Wales died in 1817. She was the daughter of the Prince Regent, later George IV and next in line to the throne after her father at the time of her death.
Edmund Smith continued in business as a sole trader at Maddox Street until 1824. The property was then occupied by Edmund and William Smith until 1846.
A peculiarity of the trade card is the position of "London" suggesting the design had previously incorporated another business location. Unfortunately no evidence has been found of it.