VBA vérifié si datePart est Dimanche

If WeekDay(Date1 ,2)=7 then Date1 = DateAdd("m", -1, Date1)

Private Sub Workbook_Open()
Application.ScreenUpdating = False
Worksheets("Relevé_Hebdo").Unprotect

Sheets("Récap_Mensuelle").Select
    If Cells(4, 1) = Empty Then

    Dim mois As String
    Dim Année As String
    Dim Titre As String
    Dim Récap_Mensuelle As String
    Dim Relevé_Hebdo As String
    Dim Semaine As String
    Dim Sme As String
    Dim c As Range
    Dim DateDepart As Date
    Dim Sunday As Integer
    Dim D As Date
    Dim j As Date
    Dim k As Date
    'Date départ au 1er du mois
    DateDepart = DateSerial(Year(Date), Month(Date), 1)
    k = DateDepart
    D = Date
    j = D + 1 - DatePart("w", D, vbMonday, vbFirstFourDays)
    mois = Format(j + 3, "mmmm") 'mois contenant au moins 4 jours de la semaine.
    Année = Format(DateDepart, "yyyy")

    Titre = "MOIS DE" & " " & mois & " " & Année
    Cells(4, 1) = UCase(Titre)

    Sheets("Relevé_Hebdo").Select
    Worksheets("Relevé_Hebdo").Unprotect
    mois = Format(j + 3, "mmmm")
    Année = Format(Now, "yyyy")

    Titre = "MOIS DE" & " " & mois & " " & Année
    Cells(1, 1) = UCase(Titre)
        If D > k Then
            D = k + 1
                Else
            D = D
        End If
            For Each c In Range("C1,E1,G1,I1,K1")
        
                j = D + 1 - DatePart("w", D, vbMonday, vbFirstFourDays)
                c = "Sem " & DatePart("ww", j, vbMonday, vbFirstFourDays)
                D = D + 7 'DateDepart = DateDepart + 7     'Incrémente la date de 7 jours (1 semaine)
        
            Next
        Worksheets("Relevé_Hebdo").Protect
    End If
    Application.ScreenUpdating = True

End Sub

 'Date départ au 1er du mois
    DateDepart = DateSerial(Year(Date), Month(Date), 1)
    k = DateDepart
        If Weekday(k, 2) = 7 Then
        k = DateAdd("m", -1, k)
        Else
        k = DateDepart
        End If

Sub test()
Dim DateDepart As Date, k As Date
DateDepart = DateSerial(Year(Date), Month(Date), [COLOR="Red"][B]2[/B][/COLOR])
k = DateDepart
If Weekday(k, 2) = 7 Then
k = DateAdd("m", -1, k)
Else
k = DateDepart
End If
End Sub

DateDepart = DateSerial(Year(Date), Month(Date), 1)
    k = DateDepart
    D = Date
        If D <> k Then
          ElseIf Weekday(D) = vbSunday Then
            k = DateAdd("m", -1, k)
          Else
            k = DateDepart
        End If