Well, don't I feel like an idiot. :-)
I was checking our flights to CSS in March. And noticed that our flight from ATL to MBJ was only 2 hours but was 4 hours on our return. We have already booked our trip to CN in November and the similar flights are 3 hours each.
So after racking my brain for a bit I realized it must be a time difference thing. And sure enough, after doing some googling, I figured out that Jamaica doesn't observe daylight savings time. ;-) Never dawned on me and I hadn't seen anything on here about it. So for those of you that might be wondering, I thought I'd post this.