I think so.
Sometimes the Angel speaks as a messager of God, like Jesus in the flesh, and sometimes the Angel speaks as God, like Jesus God incarnate.
God the Son was in existence before creation, and may also have been the voice in the burning bush.
But what may be and what we should teach as doctrine are two different things.
I would leave it as a possible understanding of the text, but other views are possible, just not mine. :)
I do not believe that the person we think of as Jesus was in eternity past. I do believe that the 2nd person of the Trinity was in eternity past who was the word of God John 1:1,14 and who apeared from time to time in Christophanies.
I am not sure there is an absolute answer although some might hold there is.
Did the heavenly host call the Word of God the Son of God before He was incarnate. I don't know. I do know scriptutre says He will be called the son, future tense.
He shall be great, and shall be called the Son of the Highest: and the Lord God shall give unto him the throne of his father David:
One can get several understandings from that and I have not mnaed up my mind. I do hold thta he was the Word in eternity past, but I am not sure of what else he was called or was considered.
Yes the Word was called the Son in Hebrews 1:8-10 as laying the foundation of the earth.
I think it is possible to view the terminology as anachronistic, using the incarnate Son name for the Word before the incarnation.