If a missing pool part comes back, or if a new non-empty pool part that we've never seen before arrives in a pool, then:
- Immediately check covefs duplication metadata consistency (the tags) and repair any damage.
- Schedule a duplication check of the entire pool.
- Flush measurement data and schedule for a remeasure.
So yes it remeasures, that's intended. We don't know what happened to the disk while it was gone, files could have been changed.