Connection timing out - SqlClient Data Provider with ADO.NET Source

I have an ADO.NET source that is selecting from a view using a connection manager of type .Net Providers\SqlClient Data Provider.  I have set the timeout to 0 in the connection manager (which I understand to mean "do not timeout ever").

When I define the view as SELECT TOP 1000 it works fine and pretty quickly, goes through all transformations, and ends up in the destination table in the database with no issues.  If I define it as SELECT TOP 1000000 or remove the TOP clause it times out after 30 seconds.  The Test Connection button returns success immediately each time.  I don't get any rows to the point of my first transformation, so it's not an error in a transformation or the destination.

I thought that a timeout would not occur at all if the SELECT had started at all.  It looks like it's timing out because no records have been returned after 30 seconds.

So my two questions are 1 - is my thought directly above incorrect, and 2 - if I'm setting timeout to 0 why is it timing out after 30 seconds?

Thanks!