Yes - for reference, it was added here: https://github.com/jakesmith/HPCC-Platform/commit/9fcf84fcc3aaab75188be7a8a939dd1436f1f74d

It *should* be anon. on attach and not anon. on detach (as with regular files).

The upshot of these calls meant superfile attach() / detach() worked once, but after detach() it became anon, and would not reattach - and was consequently missing from lookups.