Strangely enough, on both breaks I walked out of the test area and used the bathroom and ate a bit of a candy bar. When I returned, the break had expired on the computer, but the section had not started. I'm not sure how long this "grace period" exists, but to me it seemed that even though the break expired, you still had to click to continue, and thus technically had more than 5 minutes. I noticed that when I started each section, I had the full 75 minutes, so the computer didn't seem to deduct any time due to my extending my break. I'm not sure I'd rely on this though. This is just my experience.