I actually got double AP'd since I received ds-5535 and also asked to send my latest resume later that has all my studies, papers I published, my phd dissertation, etc. And my job history without any gaps.
Resume is asked for those in TAL
So I asked the officer if the country I was born (Iran) was the reason that I received ds-5535 since I never served in military neither in Canada nor anywhere else, so she said "yeah, and that your field of study and work is AI and robotics"
Looks like they see people who studied AI as a security threat. I got all my degrees—from high school to my PhD—in Canada though!