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Absolutely. They broke the 3 wheel version. A 4th wheel version was developed and key Polish math guys were helping the French break that. When France fell they were able mostly get to Britain, and worked on the new 5 wheel version.

"Enigma D was intercepted by the Poles on a Friday in late December 1927 at the Polish railroad customs house in Warsaw. A heavy package had arrived there, addressed to the German Embassy. A German representative of the "radio" company that had shipped the package, repeatedly called customs officials, stating that the package had been shipped by mistake, must not go through customs inspection, and must be returned to Berlin immediately. His calls became increasingly frantic, until custom officials became suspicious and notified the Polish Cipher Bureau, which was then responsible for radio-related matters. Polish intelligence Stefan Mayer had his agents secretly move the package to a secure location. The package contained a cipher machine visually identical with commercial Enigma machines. The agents correctly guessed that the Germans had modified the wiring; they carefully noted the changes. The machine was reassembled and returned to the radio company in Berlin. When Major Gwido Langer took over the newly organized Cipher Bureau in 1929, he possessed the modified Enigma machine, but he did not reveal this to the newly recruited mathematics students, Marian Rejewski, Henryk Zygalski and Jerzy Róźycki. Langer correctly assumed that the Germans would make further modifications to the Enigma machine, and he provided Rejewski only with a commercial machine, wanting his cryptologists to understand the machine from a purely mathematical point of view.

The German Army and Air Force Enigmas were used with several rotors; initially three. On 15 December 1938, this changed to five, from which three were chosen for a given session. Rotors were marked with Roman numerals to distinguish them: I, II, III, IV and V, all with single notches located at different points on the alphabet ring. This variation was probably intended as a security measure, but ultimately allowed the Polish Clock Method and British Banburismus attacks.

Rejewski, Marian. "How Polish Mathematicians Deciphered the Enigma", Annals of the History of Computing 3, 1981. This article is regarded by Andrew Hodges, Alan Turing's biographer, as "the definitive account" (see Hodges' Alan Turing: The Enigma, Walker and Company, 2000 paperback edition, p. 548, footnote 4.5). extracts from Wikipedia.