I would say that the scriptures do give an insight into when the event of Jesus seeing Satan falling from Heaven happened.
The seventy two say to Jesus,
"Lord,even the demons submit to us in your name."
In the reply from Jesus, he does not focus on the demons falling from Heaven,but he does focus on Satan falling from Heaven.In the book of Revelation at chapter 12:9-7 it is written,
7 Then war broke out in heaven. Michael and his angels fought against the dragon, and the dragon and his angels fought back. 8
But he was not strong enough, and they lost their place in heaven.
9 The great dragon was hurled down—that ancient serpent called the devil, or Satan, who leads the whole world astray. He was hurled to
the earth, and his angels with him.
Rev 12:7-9, informs the reader that when Satan was "hurled to earth," his angels were also hurled to earth with him.The angels are obviously "demons."
With the focus being on "demons" according to the seventy two,i feel that the text could be better understood if Jesus had replied by saying,
I saw Satan and his angels fall like lightning from Heaven.
I do not think that the fall of Satan and the fall of the angels are separate events,but it does intrigue me that Jesus does not address the demons in his reply to the seventy two.
Now to determine approximately, when this event happened the following scriptures give the reader guidance.
In the book of John at chapter 8:44, Jesus says,
"You belong to your father,the devil and you want to carry out your
father's desire.He was a murderer from the beginning."
Jesus is recalling when Cain murdered Abel (in the beginning) as referenced in Genesis chapter 4,so it is clear to the reader that Satan had already been hurled to earth.Also in Genesis chapter 3 at the "fall of man," we read that the "serpent," (who is Satan) was in the garden when he caused the fall of man.This makes it clear to the reader that Satan had already been hurled to earth at this time.
We do not have another mention of Satan on earth prior to "the fall of man,"but if the reader returns to Revelation 12 we do have a scripture that speaks about Satan being hurled to earth which alludes to the statement of Jesus in Luke 10:18.
I like to refer to this scripture as the "lightning scripture." because it is written in revelation 12:13 that,
When the dragon (Satan) saw that he had been hurled to earth,he
pursued the woman who had given birth to the male child.
My understanding of this scripture is that, at a point in time Satan was in Heaven,but Satan did not realize that he had been hurled to earth until he saw that he was on earth, which must certainly imply that Satan fell to earth "like lightning."This text again allude's to Luke 10:18 and the statement of Jesus,
"I saw Satan fall like lightning from Heaven."
And we do know from scripture that in Rev 12:5,Jesus was in Heaven and able to view, "Satan fall like lightning," for it is written,
She gave birth to a son, a male child, who “will rule all the nations
with an iron scepter.” And her child was snatched up to God and to his
throne
Now in Rev 12:12 it is written,
"Therefore rejoice,you heavens and you who dwell in them! But woe to
the earth and sea, because the devil has gone down to you! He is
filled with fury, because he knows that his time is short."
This scripture would appear to be saying that there is life in heaven at this time,
"Therefore rejoice,you heavens and you who dwell in them."
But there does not appear to be life on earth,because the scripture does not mention anyone dwelling on earth.The scripture only speaks about the earth and sea.
But woe to the earth and sea, Because the devil has gone down to you.
And because of the wording in this scripture we are given a clue as to the approximate time when Satan was hurled to earth,for it is written in Genesis 1:9-10,
9 And God said, “Let the water under the sky be gathered to one place,
and let dry ground appear.” And it was so. 10 God called the dry
ground “land,” and the gathered waters he called “seas.” And God saw
that it was good.
There is no life on earth at this time,not until Genesis 3, when God create's Adam and Eve,but the scripture in Revelation does say,
"woe to the earth and sea."
The focus is clearly on the earth and sea,and not on humans, because they have not yet been created.
Conclusion
There are two visions' received by Jesus.One is received when he is on earth,(Luke 10:-18).The other is received when Jesus is in Heaven, (Rev 12:7-9).What the reader must decide is-When Jesus replies to the seventy two with his statement,
"I saw Satan fall like lightning from Heaven."
Is Jesus receiving a Flash-Back as to when he was in Heaven with his father,?and when the father and son both viewed Satan fall to earth, or-
Is Jesus receiving a vision on earth prior to the return of the seventy two.?
From the information available to the reader through all these scripture's,it is reasonable to suggest that Jesus saw Satan fall from heaven like lightning according to the book of Revelation at chapter 12, and that the timing of the event, happened between Genesis 1:9-10,when God made the earth and sea, and Genesis 3, when the fall of man was instigated by the "serpent."