Thanks! That's a relief knowing what they really are. Contributing to my confusion was that non-active TFRs are also yellow and the effective height labels associated with each drop zone.
I've identified the drop zones from the 2nd picture above on the sectional picture below. Two questions pertaining to the EFIS's display of the drop zones (I looked in the 4500's manual, v7.4, and there was no mention that I could find):
1 - What's the difference between segmented vs solid circle?
2 - How come one shows up as 155/SFC and the other as 15 AGL/SFC?