Hi,
You use the same process to expire backups with puredisk (right click the image in the catalog and select expire, or via bpexpdate on CLI). The thing is that in PureDisk you might not see a reduction in space of X as you would expect. Remember its deduplicated, so the content that you're expiring was hashed and broken into a million pieces, subsequently as more backups were performed to your puredisk pool, other backups got deduplicated on the basis that the hash (bits) they contain were already in the pool (provided by the content you want to expire). So now if you expire, it might not release all the hashed data because other images depend on it.
