I Keep getting thrown a Error 9 when Working with a Variant Array

This code is checking a file name against a array to determine if we need to operate on that file.
Code breaks when i attempt to explicitly assign array size. If i do not do that, code breaks during the string check saying If arr(i) is out of range of the array.

Not sure why, UBound and LBound works perfect, and the array is being assigned correctly from the local properties list.

'Loop through all files in Folder
Do While TargetString <> ""
    Set SourceWB = Workbooks.Open(NavigationString & TargetString)

    'This checks how full our list is and appends the array correctly
    BankWS.Activate
    'There is more than 2 items, append full list to array
    If Not BankWS.Range("I3") = "" Then
        BottomOfList = BankWS.Range("I2").End(xlDown).Address
        OldReportsArray = BankWS.Range("I2:" & BottomOfList).Value
    Else
    'There is a single item or empty, append 1st value and empty 2nd
        OldReportsArray = BankWS.Range("I2:I3").Value
    End If
ReDim Preserve OldReportsArray(UBound(OldReportsArray) + 1)
'Check Array and SourceWB to see if we have already loaded in this report
    If IsInArray(SourceWB.Name, OldReportsArray) = True Then
        'Match found, Skip to next loop iteration
        SourceWB.Close
        GoTo NextLoop
    End If`

'Check Passed String inside of Array, return true or false
Public Function IsInArray(stringToBeFound As String, arr As Variant) As Boolean
    Dim i
    For i = LBound(arr) To UBound(arr)
        If arr(i) = stringToBeFound Then
            IsInArray = True
            Exit Function
        End If
    Next i
    IsInArray = False
End Function