These key off the interior color of the destination cell, i.e. Yellow

If you wanted something different, like "Prior Actual" in col F and the second of each month-pair that could be done similarily

Option Explicit


Sub InsertAsFormula()
    Dim rData As Range, rCell As Range
    Dim bScreen As Boolean, bCalc As XlCalculation
    
    bScreen = Application.ScreenUpdating
    bCalc = Application.Calculation
    
    Application.ScreenUpdating = False
    Application.Calculation = xlCalculationManual
    
    
    With ActiveSheet
        Set rData = Intersect(.UsedRange, .Cells(7, 8).Resize(, 24).EntireColumn)
    End With
    
    For Each rCell In rData.Cells
        With rCell
            If .Interior.Color = vbYellow Then
                .Formula = "=" & .Offset(0, -1).Address
            End If
        End With




    Next
    
    Application.ScreenUpdating = bScreen
    Application.Calculation = bCalc
    
    MsgBox "Done"


End Sub


Sub InsertAsValue()
    Dim rData As Range, rCell As Range
    Dim bScreen As Boolean, bCalc As XlCalculation
    
    bScreen = Application.ScreenUpdating
    bCalc = Application.Calculation
    
    Application.ScreenUpdating = False
    Application.Calculation = xlCalculationManual
    
    
    With ActiveSheet
        Set rData = Intersect(.UsedRange, .Cells(7, 8).Resize(, 24).EntireColumn)
    End With
    
    For Each rCell In rData.Cells
        With rCell
            If .Interior.Color = vbYellow Then
                .Value = .Offset(0, -1).Value
            End If
        End With




    Next
    
    Application.ScreenUpdating = bScreen
    Application.Calculation = bCalc
    
    MsgBox "Done"


End Sub