Hey there Marko, welcome to the forum!
It is clear from the ancient DNA record that branches of J2b-Z38240, such as J2b-PH1602, were historically most concentrated in the Dalmatian coast and adjacent areas in the (north-)western Balkans, being especially associated with the Cetina culture and later derived Illyrian populations. It is clear from the current data that these Illyrian populations did not play a major role in the genetic formation of the Albanians, rather southern Illyrian peoples that were not as heavy in J2b-Z38240 fulfilled this role. Branches of J2b-L283 best associated with the ancestors of the Albanians include: J2b-PH4679, J2b-Y82533 etc.
I believe that J2b-Y40852 could represent a line that expanded southwards during the Roman period and was eventually Romanised, expanding with Balkan Romance groups that would eventually develop into the Vlachs who would consequently spread it.