Location of main server for Ubuntu

[Basil Chupin]

Being new to Ubuntu I don't know the answer to this question which would 
have been asked and answered probably many times before:

in which part of the world is the main server located for Ubuntu releases?

I know that Canonical is a Europe based company, but where are the 
servers located?

Reason for asking: when it is stated that Ubuntu Beta 2, say, is 
scheduled for release on 8 April is this as per the date in Europe or 
the date somewhere to the west of London? In a couple of hours here 
(east coast of Australia) it will be 9 April and in 11 hours in London 
it will also be 9 April but to the west it will still be 8 April......

(Is there a "usual" hour of the day when a release is available from the 
main server? morning, around noon, evening...?)

BC

-- 
In a period of great joy and pleasure you are comforted by the thought that tragedy is just around the corner.