It has long been debated whether speech production and perception remain flexible in adulthood. The current study investigates the effects of language dominance switch in Galician new speakers ( neofalantes) who are raised with Spanish as a primary language and learn Galician at an early age in a bilingual environment, but in adolescence, decide to switch to using Galician almost exclusively, for ideological reasons. Results showed that neofalantespattern with Spanish-dominants in their perception and production of mid-vowel and fricative contrasts, but with Galician-dominants in their realisation of unstressed word-final vowels, a highly salient feature of Galician. These results are taken to suggest that despite early exposure to Galician, high motivation and almost exclusive Galician language use post-switch, there are limitations to what neofalantescan learn in both production and perception, but that the hybrid categories they appear to develop may function as opportunities to mark identity within a particular community.