VS 2010 UpdatePanel - Update Twice In Same Routine

I'm trying to do a number of large queries in the same routine, and have a label in an updatepanel update after each one. I must be doing something wrong, however, because whenever I fire up the routine, my label won't update until the last query is done. Isn't it possible to do UpdatePanel.Update multiple times in the same routine/event? This is the code I'm using:

Protected Sub Button1_Click(ByVal sender As Object, ByVal e As EventArgs) Handles Button1.Click
lblStatus.Text = "Busy with task 1"
UpdatePanel1.Update()
LongTask()
lblStatus.Text = "Busy doing task 2!"
UpdatePanel1.Update()
LongTask()
lblStatus.Text = "Done!"
UpdatePanel1.Update()
End Sub

Private Sub LongTask()
conn = New SqlConnection(connstring)
conn.Open()
cmd = New SqlCommand("Select * from very_large_table", conn)
cmd.CommandType = CommandType.Text
reader = cmd.ExecuteReader()
End Sub

When the form loads, the lblStatus is emtpy. When I click the button, I see the page loading until it displays 'Done!'. I don't see the other texts. This is the page source:

<%@ Page Language="VB"
MasterPageFile="~/MyApp.master"
AutoEventWireup="false"
CodeFile="test_page.aspx.vb"
EnableEventValidation="false"
Inherits="test_page"
title="MyApp"
Theme="DefaultTheme"
%>
<asp:Content ID="Content1" ContentPlaceHolderID="ContentPlaceHolder1" Runat="Server">
<asp:UpdatePanel ID="UpdatePanel1" runat="server" UpdateMode="Conditional">
<ContentTemplate>
<asp:Label ID="lblStatus" runat="server"></asp:Label>
<asp:Button ID="Button1" runat="server" Text="Update!" onclick="Button1_Click" />
</ContentTemplate>
</asp:UpdatePanel>
</asp:Content>

The page has a masterpage that contains the neccesary Scriptmanager.