Daniel Erker is Associate Professor of Spanish and Linguistics at Boston University and director of The Spanish in Boston Project. His research interests include language variation and change, sociolinguistics and multilingualism. Gregory R. Guy is Emeritus Professor of Linguistics at New York University and has authored studies of sociolinguistic varieties of Portuguese, Spanish and English. His research addresses social, geographical and diachronic diversity in language and linguistic variation theory. Karen V. Beaman is Research Associate and Lecturer in Quantitative Linguistics at the University of Tübingen, focusing on language variation, coherence, and change. She is the author of Language Change in Real-and Apparent-Time: Coherence in the Individual and the Community (2024). Robert Bayley was a Distinguished Research Professor of Linguistics at the University of California Davis. He was the author of more than 160 publications, including The Hidden Treasure of Black ASL: its History and Structure (with C. McCaskill et al. 2020). Aria Adil is Professor of Linguistics at the Department of Romance Studies at the University of Cologne. His work centers on grammatical variation, including syntactic, pragmatic and social-cultural aspects, aiming to conduct research with societal impact. Rafael Orozco is Professor of Linguistics and Spanish at Louisiana State University. He is the author of Spanish in Colombia & New York: Language Contact Meets Dialect Convergence (2018) and researches variationist sociolinguistics with emphases on Latin American Spanish and Spanish in the United States. Xinye Zhang is a research affiliate at the Department of Linguistics, University of California, Davis. Her research focuses on sociolinguistics, second and heritage language acquisition, and language variation perception.