Thanks for your enthusiasm!
This month we visited the ledge to spruce things up a little in and around the nest box in preparation for the 2014 nesting season. It's always more pleasurable to get our chores completed when the weather is nice, that particular day was sunny and warm (although no peregrines came to supervise us as we worked). We removed the soiled gravel and replaced it with new. Within one day's time Durand had already visited the box to create multiple scrapes (depressions) in the gravel to put her own touches on things. At some point we'll make another trip to paint the box.
In the meantime, we assume that Zoom has successfully migrated out of the area and hopefully is doing well wherever her travels take her. Spark and Durand will likely stay in the Columbus area for the winter occasionally checking in at the ledge, so sightings will be by chance.