You’re correct. Buddha images of the Ayutthaya
Style can be divided into 4 sub-periods. At first the second and third U-Thong styles of Buddha image were
Popular in Ayutthaya. In fact the large buddha image Wat Phanan Cherng,Luang Phor To which was built 26 years before the foundation of the city, belongs to the
second period of the U-Thong style. The real Ayutthaya style began about the middle of the 15th century in the
Reign of King Boromtrailokanart.