maximum time to submit the RFE documents requested???

What is the maximum time to submit the RFE documents requested???

My RFE statu showed from Sept 29th and still my organisation did nt take any step to produce the client letter.

What would be last date to submit the documents?

In the RFE document, it is mentioned till when response can be submitted. Duration is also not standard and vary across RFEs.

My RFE was raised on Sep 28, 2012 and last date to submit the response was Dec 21st, 2012.