From the Banister Family Collection at the University of Bristol - Historical Photographs of China website: https://www.hpcbristol.net/visual/ba06-100
Text: The first building on the left is Jardine House (Jardine, Matheson & Co) - a building which was demolished in 1907. Painted advertisements: SMOKE SHEE[...] CIGARETTES / PUREST AND BEST; TRY HEINZ APPLE BUTTER; HEINZ 57 GOOD THINGS; THE MUTUAL STORES.
Behind Jardine House should be the P&O Building (3rd gen)
The building under construction is possibly the new Post Office. Although it opened in 1911, and Jardine House was demolished in 1907, the date could be around 1906-07.
Probably taken from the Hotel Mansions / Union Building.