"Wahawi ya Wahawi Eyaha": Is it an Ancient Egyptian Chant?

My vacation begins today. As I did last year, I've prepared a series of posts ahead of time on historical, cultural, and linguistic topics that are not time-constrained. If events warrant, I will add current posts, but at least one new post will appear daily in my absence. Enjoy.

It's Ramadan, and back before Ramadan was primarily associated with  television soap opera series, the tradition in Egypt was to light fanous, Ramadan lanterns. The fanous were associated with a popular chant, beginning "Wahawi ya Wahawi Eyaha,"  More recently the phrase was expanded into a popular song. The question is, where does the phrase come from? It doesn't have any obvious meaning in Arabic, so the assumption that it is pre-Islamic is a reasonable one; after all, many ancient folk customs survive, and one is coming up next week, Wafa' al-Nil, the feast marking the Nile flood, which goes back to Pharaonic times.

Lately two different Egyptian English language news sources have cited a Pharaonic etymology for 'Wahawi ya Wahawi in their features for Ramadan. Both offer the same basic explanation, and I'm wondering if this is a real etymology with some sort of documentation, or a folk etymology:

Salonaz Sami in Al-Ahram:

For as long as I can remember, even when I was a kid and into my adolescent years, I have wondered about the meaning of eyaha. It wasn't until recently that I found out that eyaha, actually taken from the ancient Egyptian, means "moon". The phrase was used in ancient times in honour of Eyaha, the mother of the Pharaoh Ahmose I, who expelled the invading Hyksos from Egypt when he was just 16 years old. Wahawy ya wahawy, eyaha, means something like "welcome Eyaha". Since Muslims worldwide use the moon to determine the beginning and end of the holy month, the use of this phrase makes perfect sense. 

Nabila Magdy in Egypt Independent:

King Ahmose I, the founder of the 18th dynasty, expelled the Hyksos only five years after he ruled Egypt in 1550 BC at the age of 16. The story goes that whenever the people saw Queen Eyaha, whose name meant “moon,” they would sing “Wahawy, Eyaha,” meaning “Welcome, Ehaya.”
Ever since, Egyptians have used the same song to celebrate different occasions. As the Islamic hijri calendar follows the lunar system, Egyptians living in the Fatimid era, from AD 969 to 1171, started to celebrate the beginning of the holy month of Ramadan by singing “Wahawy, Eyaha” — a tradition that has continued today.

Let's analyze this story. Since neither report sources it, and it sounds a bit like a folk etymology,

First, the phrase does seem to have something to do with the moon, and the "welcome, moon" explanation in the first account makes sense, "Moon" was iah in Ancient Egyptian and yoh in Coptic, so the Eyaha part, which has a vowel somewhere between a and o, probably does have to do with the moon. Coptic is just the late form of Ancient Egyptian, and thus an Egyptian phrase is presumably involved. But how old is it?

Second, the mother of the Pharaoh Ahmose I is generally held to have been Ahhotep, the name meaning "the Moon is satisfied" (as "Ahmose" means "born of the moon,"), so her name did incorporate the moon in it, even if she was not exactly called "Eyaha."

But "welcome, moon" seems a reasonable call for Ramadan, and both stories link its use to the Fatimid era and other stories specifically link it to the era of the Fatimid Caliph al-Hakim bi-Amr Allah (996-1021 AD). At that period Coptic was still very much a spoken language, so why not just assume it's a Coptic phrase? Why attribute it to a remote queen of Egypt? Is this a folk etymology or a real one?

First, I'm not sure, so if anyone has documentation to linking this to pharaonic times rather than just the Middle Ages

Note that the headline on the Egypt Independent article says "Ramadan Jingle is 6,000 Years Old." As an editor I'm well aware authors aren't always responsible for their headlines, but how do we get to 6000 years?  The conventional date for the unification of Upper Egypt and the start of the First Dynasty is 3100 BC, which is 5100 years ago, but Ahmose I's reign is placed around 1550 BC, which means the story told here is claiming an age of only 3,500 years or so.

One clue that this may be a folk etymology is that it doesn't seem to make a lot of sense in context. Why would Ancient Egyptians have greeted their queen (a divine being, remember) so infomally? Why would the greeting somehow have been associated with holidays, Ramadan or other? On the other hand, "welcome moon" needs no great explanation, no ancient queens, to make sense. If anyone has got a clear document linking the phrase to Ahmose I, post it as a comment. Here, however, is what the chant sounds like, in modern song form: