Message from FEMA. I don't think it is posted anywhere but they responded to an email of ours.
The SFHDF (FEMA Form 81-93) has a revised expiration date of October 31, 2008 and was approved for use, effective December 2005. There were no changes to the format or content of the SFHDF.
"An electronic version of the SFHDF and instructions are available on the FEMA website at
http://www.fema.gov/business/nfip/forms.shtm. To allow users of the time to update their systems to the new version, the effective date for mandatory use of the new Form is July 1, 2006. Although the old version (expiration date October 31, 2005) of the SFHDF is no longer available for distribution, existing copies may be used until June 30, 2006. SFHDFs completed on or after July 1, 2006, must be completed using the new form, for compliance purposes."