I submitted FOIA request but it was denied after two months, since I did not provided adequate identifying personal information. In those two months, I called FOIA and after several conversations with different departments, I was finally able to navigate to a FOIA representative. She told me that FOIA requests can be fulfilled within 2 months to 2 years (or may be more), depending on your case and availability of records and various port of entries to the US.
I did not waited for receiving response from FOIA, and I opened a ticket with CBSA to get entry exit records between Canada and the US. I received those records in about 5 weeks. When I was sending those records to CIC, I also attached I-94 records and all itineraries for which more than 24 hours were spent outside Canada, and it worked.