Jackson (1967: 489 f.) already noted that the Breton dialect of the island of Ushant seemed to have retained Late PBr. *dl, *dr as dl, dr, and not (e)l, (e)r like in the other MoB dialects, e.g. Ushant dialect (U) [ˈgɥẹdrẹn] ‘glass’ vs. MoB gwerenn, U [maˈdrunɛs] ‘godmother’ vs. MoB maeron(ez), and U [ˈkodlɛ] ‘young bull’ vs. MoB kole. Jackson (1967: 496 f.) suggested that the development Late PBr. *dl, *dr to U dl, dr only seems to have taken place in polysyllabic words and persuasively argued for the intermediate stage of *ðdl, *ðdr. His theories regarding this development are not all-encompassing, however, and fail to convincingly explain exceptions like U [ˈkɛlu] ‘news’ (MoB keloù) and U [ˈlɛrɛnː] ‘thong’ (MoB lêrenn). Using the evidence from the Atlas Linguistique de la Basse-Bretagne (Rennes 1924) (ALBB) and two tables consisting of all Ushant dialect words from Malgorn’s article Le dialecte d’Ouessant (1909) and the Nouvel Atlas Linguistique de la Basse-Bretagne (NALBB), I have been able to provide a new and accurate chronology for the development of Late Pr. *dl, *dr to U dl, dr. All Ushant dialect words that are central in this discussion can be found in the appendix at the back of the article. In this appendix one can find the position of the word in the appendices of my MA thesis and/or the ALBB, as well as the MoB form, the Middle Breton form (if attested), and an English translation.