I recently used the Cobras Export and Import tools found at http://ciscounitytools.com to perform a physical to virtual migration and upgrade from Unity Connection 8.6 to 11.5.
One issue I found was that schedules with multiple details weren't imported completely. I don't know if this is an issue with the export or the import process or possibly with the Connection versions but after checking the target 11.5 cluster I found only the first detail in the schedules with multiple details was restored.
It may also be worth noting that all the detail in each of the affected schedules were named the same, for example "Detail for All Hours - All Days" used multiple times to describe individual detail for each day. I don't remember seeing anyone use this technique elsewhere so it may also have been a contributing factor.
Lesson learned: check your schedules after your import is complete.
The Cobras Export for Connection version was 8.0.76 and Import for Connection was 8.0.92.