When upgrading to SharePoint 2013, there is an option to view the SharePoint 2010 sites as an evaluation copy in order to correct layout and format. The url of this site will be different than the copied site, and this may break the link to externalized BLOBs if content is copied.
The Metalogix Archive Adapter is not compatible with Endpoint Start Folder, when configuring the storage profile.
Content that is uploaded using PowerShell or some other third party tool will create extra BLOBs in the system cache. If this method is used, running the Unused BLOB cleanup will take care of the extra BLOBs.
After performing a Bulk Recall, it may be necessary to run the Unused BLOB Cleanup job to remove BLOBs from the endpoint. The Bulk Recall no longer removes blobs if they have not passed the BLOB retention period.