@brian, I was doing manual checking. Then I get redirected to this URL https://www2.mcneel.com/updates/60515f84-8f7f-41da-801d-1c87e32f88f5/release/win64/en-us/stable/5.4.30524.11065
Today, on that page it still shows the following link as the most recent version available http://files.mcneel.com/dujour/exe/20131028/rh50Release_x64_en-us_5.6.31028.18305.msi
As you can see this is 5.6, not 5.7.