thanks for your reply. According to your recommendation, we won't be doing reverse incrementals.
If you can easily point me to the existing discussion you're referring to, I'd love to read it.
But I can't get the Fast Clone to work on this job
it's probably because the repository was first created in NTFS and subsequently formatted in ReFS, but it's definitely well-recognized now ("align blocks" greyed out).
No existing ntfs-made backups were left, I created a chain from scratch expecting it would fast-clone.
When it didn't, I performed a Compact, no avail.
Now it's just ran its first Synth Full, and well ... it took over 30 hours (12TB) and no sign of fast cloning in the logs.
Where can I look and can I do anything except start from scratch (delete repo, start new chain)? I'll open a tech case later today.
PS and totally unrelated: I'm not a twitter hero so I hope you got my message about Nine Email for Android