Read this and answer the question. If the question is unanswerable, say "unanswerable".

The evolution of Proto-Greek should be considered within the context of an early Paleo-Balkan sprachbund that makes it difficult to delineate exact boundaries between individual languages. The characteristically Greek representation of word-initial laryngeals by prothetic vowels is shared, for one, by the Armenian language, which also seems to share some other phonological and morphological peculiarities of Greek; this has led some linguists to propose a hypothetical closer relationship between Greek and Armenian, although evidence remains scant.

What progression coincided with the the early Greek states that makes it difficult to give credit for the language and differences ?
Paleo-Balkan sprachbund that makes it difficult to delineate exact boundaries between individual languages.