Whenever classified records are withheld, there is a process called Mandatory Declassification Review that can be sought to remove redactions or release documents.
The Lawyers’ Committee has undertaken the following MDRs beginning in MAY 2017. The MDR process has now expired (one year in JUL 2018) and an appeal has been launched with the Interagency Security Classification Appeals Panel (ISCAP)
https://www.archives.gov/declassification/iscap/mdr-appeals.html
Click the following Index to review the six consecutive requests
9/11 Commission SC Master Box A
9/11 Commission SC Master Box B
9/11 Commission SC Master Box C
9/11 Commission SC Master Box D
9/11 Commission SC Master Box E
9/11 Commission SC Master Box F