Excel VBA - Highlight cell if time is greater than 24 hours ago - vba

Question

I have a report that will generally be run everyday just after 7am, but occasionally could be run later during the day. In col D are ticket update times/dates. If the ticket was updated yesterday, then the cell should be left alone; if the ticket was not updated yesterday (IE, if today is the 3rd, and it has not been updated since X o'clock on the 1st) the cell should highlight. Since the report will occasionally not be run until later in the day, I can't do a simple CurrentTime - 24 hours to figure this out. I need the function to always look for the previous day and before 7am.
Without knowing exactly how to code this, I know it should be something like:
If ticketUpdateTime < currentDay at 0700 - 24
Then highlight (I know the code for this part already)
End If
Hopefully this makes sense

Answer 1

If DateDiff("h", CDate(ticketUpdateTime), CDate(Format(Now(), "mm/dd/yy")) + TimeSerial(7, 0, 0)) > 24 Then
highlight
End If
In plain English:
If the time elapsed between ticketUpdateTime and today's date at 07:00AM is more than 24 hours, highlight
It's a bit out of scope for the original question, but here's usage example as well:
Sub CheckTimes(rng As String)
Dim someRange As Range, someCell As Range
Set someRange = Range(rng) ' Convert input string to an actual range object
For Each someCell In someRange
If DateDiff("h", CDate(someCell.Value), CDate(Format(Now(), "dd/mm/yy")) + TimeSerial(7, 0, 0)) > 24 Then
Debug.Print "Highlight"
End If
Next cell
End Sub
To call it, input Call CheckTimes("D2:D100") or whatever range you need
Mind that there's no error-checking/-handling or data validation here - you'll have to do that yourself. ;-)

Answer 2

You may use dateserial(Year as integer, month as Integer, day as Integer) and TimeSerial(Hour as Integer, Minute as Integer, Second as Integer). I don't know how exactly you ticketUpdateTime looks like, so its hard to write expression. However, previous day 7 am would be:
dateserial(year(date-1), month(date-1), day(date-1)) & " " &timeserial(7, 0, 0)

Answer 3

Appears to be an of issue. All of the dates/times are yesterday except for the value in D2 which is 11/01/2017 10:47:02, and that value is not highlighting.
Call CheckTimes("D2:D" & lastRow)
Sub CheckTimes(rng As String)
Dim someRange As Range, someCell As Range
Set someRange = Range(rng) ' Convert input string to an actual range object
For Each someCell In someRange
If DateDiff("h", CDate(someCell.Value), CDate(Format(Now(), "dd/mm/yy")) + TimeSerial(7, 0, 0)) > 24 Then
someCell.Interior.Color = 16750899
End If
Next someCell
End Sub