South Upi, officially the Municipality of South Upi, is a municipality in the province of Maguindanao del Sur, Philippines. According to the 2020 …South Upi, officially the Municipality of South Upi, is a municipality in the province of Maguindanao del Sur, Philippines. According to the 2020 census, it has a population of 43,197 people. It also known as Timanan.