How I change vba code for to one time zone central time zone only

[TLS49]

Private Sub CHANGE_TIME_Click()
Dim Tm, TimeRng
    Dim Tminus As Double
Application.ScreenUpdating = False
Set TimeRng = ThisWorkbook.Sheets("Schedule and Teams").Range("F2:F273")
''*****************************************************************
 Select Case MsgBox("Please, click ""YES""to Convert time to Central" & vbNewLine & "OR click ""NO"" to Convert time to Pacific" & vbNewLine & "Click ""CANCEL"" to end macro", vbYesNoCancel, "TIME ZONE OPTION")
      Case Is = vbYes
        Tminus = 1 / 24
      Case Is = vbNo
         Tminus = 3 / 24
      Case Is = vbCancel
      Exit Sub
     End Select
''***********************************************************
    For Each Tm In TimeRng
        If IsNumeric(Tm.Value) And Tm.Value <> "" Then
                Tm.Value = Tm.Value - Tminus
        End If
    Next Tm
TimeRng.EntireColumn.AutoFit
''*******************************************
Sheets("Schedule and Teams").Activate
ActiveSheet.Range("A1").Activate
Application.ScreenUpdating = True
Sheets("Schedule and Teams").Visible = True
Sheets("Schedule and Teams").Select
End Sub

How I change code one time zone only without message box pop up

 

[johnnyL]

How about:

Private Sub CHANGE_TIME_Click()
Dim Tm, TimeRng
    Dim Tminus As Double
Application.ScreenUpdating = False
Set TimeRng = ThisWorkbook.Sheets("Schedule and Teams").Range("F2:F273")
''*****************************************************************
'' Select Case MsgBox("Please, click ""YES""to Convert time to Central" & vbNewLine & "OR click ""NO"" to Convert time to Pacific" & vbNewLine & "Click ""CANCEL"" to end macro", vbYesNoCancel, "TIME ZONE OPTION")
''      Case Is = vbYes
        Tminus = 1 / 24
''      Case Is = vbNo
''         Tminus = 3 / 24
''      Case Is = vbCancel
''      Exit Sub
''     End Select
''***********************************************************
    For Each Tm In TimeRng
        If IsNumeric(Tm.Value) And Tm.Value <> "" Then
                Tm.Value = Tm.Value - Tminus
        End If
    Next Tm
TimeRng.EntireColumn.AutoFit
''*******************************************
Sheets("Schedule and Teams").Activate
ActiveSheet.Range("A1").Activate
Application.ScreenUpdating = True
Sheets("Schedule and Teams").Visible = True
Sheets("Schedule and Teams").Select
End Sub