This sociolinguistic study focuses on a phonological variation of [u] in the “Town Speech” of Lishui County (Jiangsu Province, China) in the apparent-time paradigm with four age cohorts. The (u)-variation in the Town Speech of Lishui is a change-in-progress toward Putonghua and is unevenly distributed in the phonological and the lexical systems and across age cohorts. As a change-in-progress, it redistributes high-back vowels and glides in some word classes. While no Putonghua phonemes have been imported, the changes have been going through a series of approximations toward the phonological system of Putonghua. Consequently, the changes are transforming the Town Speech of Lishui into a localized Putonghua, or more precisely, a Putonghua-like dialect. It is an intermediate variety closer to the original local dialect than to Putonghua on a scale with Putonghua on one extreme and the dialect on the other.