Android Question GPS Leap Seconds and wrong time

#Region Project Attributes
#MainFormWidth: 300
#MainFormHeight: 300
#End Region

Sub Process_Globals
    Private fx As JFX
    Private MainForm As Form
    Private xui As XUI
    Private Button1 As B4XView
    Private UDPSocket1 As UDPSocket
    Private NTPPort As Int = 123
    Private NTP1970 As Long = ((1970 - 1900) * 365 + 17).As(Long) * 86400
    Private NTPTimeStamp(4) As Double
End Sub

Sub AppStart (Form1 As Form, Args() As String)
    MainForm = Form1
    MainForm.RootPane.LoadLayout("Layout1")
    MainForm.Show
    UDPSocket1.Initialize("UDP", 8000, 8000)
End Sub

Sub SendNtpRequest(NTPServerName As String)
    Dim data(48) As Byte
    data(0) = 0x1B 'This sets the first byte to 27 (00011011 in binary), which is the NTP request format
    Dim Packet As UDPPacket
    Packet.Initialize(data, NTPServerName, NTPPort)
    NTPTimeStamp(4) = 0 ' Reset this to check if we receive a reply
    NTPTimeStamp(1) = DateTime.Now ' Record the time when the request is sent
    UDPSocket1.Send(Packet)
End Sub

Sub UDP_PacketArrived (Packet As UDPPacket)
    If Packet.Length < 48 Then Return ' Ensure we have enough data
    NTPTimeStamp(4) = DateTime.Now ' Record the time when the response is received
    Dim StartFrom As Int = Packet.Offset + 32 ' Start reading from the 32nd byte for time data
    For ServerTimeStamp = 2 To 3
        Dim Temp As Long = 0
        For I = StartFrom To StartFrom + 6 '7 bytes for each timestamp (32 bits seconds + 24 bits fraction)
            Temp = Bit.ShiftLeftLong(Temp, 8) + Bit.And(Packet.Data(I), 0xFF)
        Next
        Dim NTPSeconds As Double = Temp / 0x1000000 ' Convert to seconds, shifting binary point 24 bits left
        NTPTimeStamp(ServerTimeStamp) = (NTPSeconds - NTP1970) * 1000 ' Convert to Java ticks (ms since 1970)
        StartFrom = StartFrom + 8 ' Move to next 64-bit timestamp
    Next
    ProcessNTPTime
End Sub

Sub Button1_Click
    Dim NTPServerName As String = "au.pool.ntp.org" ' Use an Australian NTP server
    SendNtpRequest(NTPServerName)
    Sleep(2000) ' Wait for response - adjust this if needed
    If NTPTimeStamp(4) = 0 Then
        Log("No reply from " & NTPServerName)
        Return
    End If
    ProcessNTPTime
End Sub

Sub ProcessNTPTime
    Dim LocalTimeMiddle As Double = (NTPTimeStamp(1) + NTPTimeStamp(4)) / 2
    Dim ServerTimeMiddle As Double = (NTPTimeStamp(2) + NTPTimeStamp(3)) / 2
    Dim DeviceToNTPOffset As Double = ServerTimeMiddle - LocalTimeMiddle
   
    Dim Direction As String = If(DeviceToNTPOffset < 0, "ahead of", "behind")
    Log("Device clock is " & NumberFormat2(Abs(DeviceToNTPOffset), 1, 1, 1, False) & " ms " & Direction & " NTP server time (roundtrip " & NumberFormat2(NTPTimeStamp(4) - NTPTimeStamp(1), 1, 1, 1, False) & " ms)")
   
    DateTime.TimeFormat = "hh:mm:ss.SSS"
    Dim N As Long = DateTime.Now
    Log("Device clock = " & DateTime.Time(N))
    Log("NTP clock = " & DateTime.Time(N + DeviceToNTPOffset))
End Sub

        Dim Temp As Long = 0
        For I = StartFrom To StartFrom + 6 '7 bytes for each timestamp (32 bits seconds + 24 bits fraction)
            Temp = Bit.ShiftLeftLong(Temp, 8) + Bit.And(Packet.Data(I), 0xFF)
        Next
        Dim NTPSeconds As Double = Temp / 0x1000000 ' Convert to seconds, shifting binary point 24 bits left
        NTPTimeStamp(ServerTimeStamp) = (NTPSeconds - NTP1970) * 1000 ' Convert to Java ticks (ms since 1970)