Erichthonius or Theseus, who established the Panathenaea?

The sources know two versions of the establishing of Panathenaia, the main public holiday of the Athenian polis. The earliest version of aition of Panathenaia is associated with the history of the Athenian indigenous king Erichthonius. The son of Gaia and Hephaestus, Erichthonius was raised by the goddess Athena on the Acropolis, and after becoming king of Athens, he dedicated the feast of Panathenaia to the goddess. In the source, he is the first founder of the holiday. However, two types of Panathenaia were known in Athens: the Lesser Panathenaia, which were held annually, and the Greater Panathenaia, which, like the Olympic Games, were held every four years. Gradually, there appear pieces of new information about the history of the establishing of the Panathenaia in the mythological tradition. Now the authors distinguish two stages in the history of the feast, wherein the earlier one was called Athenaia. Gradually Erichthonius was relegated to the background, as founder Athenaeus, whereas the holiday got a new name - Panathenaia. This process was often associated with the synoekismus of Theseus, when he had united all the Athenians into one urban community. The cult of Theseus became especially popular in Athens after the reforms of Cleisthenes. Theseus' exploits are becoming a popular theme in Attic vase painting, especially scenes depicting the struggle, which Theseus was believed to be the founder of in Athens. At the same time, the program of the Panathenaic Games was expanding, the Panathenaia gradually acquired a supra-regional character.