HTTP 1.1 responses can be chunked (spec). At the end of the last chunk the server can send a "trailer", which contains additional headers.
The question is: can you include a Location header in the trailer, and will the browser react by making a redirect?
The problem is that Location header to work should be with specific response code 3xx so in a standard response you can’t use it see http://www.w3.org/Protocols/rfc2616/rfc2616-sec14.html