DOJ amended guidelines to executive agencies not to withhold information strictly for procedural reasons. This applies to CBP. The goal appears to be both accelerate administrative efficiency and narrow number of denials.
Two years ago, I made a FOIA request to CBP at Dallas Fort Worth. It took them just under two months to respond. How this will play out remains to be seen.
For more information go to http://www.justice.gov/opa/pr/2009/March/09-ag-253.html