With currently available data we can say that from Neolithic to Late Chalcholithic modern Armenia was inhabited by Armenian like people shifted to East Med. In LC period the shift toward East Med became even more stronger. You can see LC period sample from Azerbaijan ploting close to Arslantepe LC samples. On the other hand we have Armenia Chl ( marked as LCaucasus_C) which is shifted toward North East ( to left and top) This is because it has some Steppe Piedmont type ancestry which should not be confused with Yamna. If we remove that shift they will also plot close to other LC samples from Turkey and Azerbaijan. This Areni was exceptional and we should not imagine it as a widespread type of ancestry in historic Armenia. They had trade contacts with North.
Then in EBA (after 3600bc) with Kur Araxian culture we had a serious shift toward CHG. While modern Armenians are in intermediate position between EBA and LC. The most top red circle of Arslantepe LC is the place of modern Armenians. ( It is the ART018 sample)
How this became possible?
The answer to this question can be found in Kur Araxian samples from Arslantepe. Here how they look.
Target: TUR_Arslantepe_EBA (Kur Arax)
Distance: 1.2158% / 0.01215811
This means that those CHG shifted KurAraxians had quite little genetic impact on southern and western parts of Arm. Highland were mostly the preceding LC type simply borrowed the KA culture without having much genetic ancestry from this people.
PS. The shift toward CHG do not mean that KA people came from Caucasus. In most likelihood they are from Kars Artahan Javakhk region were isolated highlanders were living. KurAraxian from Kaps (Shirak) is the best proxy for this proto Kur Araxians. From linguistic point of view this also means that KA was a multiethnic place.