is all written down in the "Reexam Request for Extension of Time" posted in the IFW of the '336 (90/008,474).
Here's my "Readers' Digest" version:
The mailing of the NIRC during the week of Aug. 17 was a reasonable "guesstimate" by Henneman based on the info contained in the Interview Summary received on Aug. 13 by fax (posted on Aug. 14 in IFW "Applicant summary of interview with examiner"). He writes that the examiner informed him that a NIRC will be prepared after internal proceedural matters are concluded which was expected to be in the week of Aug. 17.....no OFFICIAL DATE of the mailing was EVER stated by the USPTO.
I humbly suggest that you read the request and the summary interview to get the full novel.
GLTAL