Zxfer doesn't distinct snapshots with the same name (?)

[ant5]

Hello and thank you for your work first of all!

I'm migrating to ZFS (FreeBSD) and creating simple backup system with dedicated backup host.

Snapshots on production are created by periodic-snapshot with names hourly.0, daily.0 etc.
Then I use zxfer to transfer dataset and related snapshots to backup host. Initial transfer was fine. But next invocations do nothing.

Production host:

NAME                  USED  AVAIL  REFER  MOUNTPOINT
ps1/mboxes@weekly.2   626M      -   157G  -
ps1/mboxes@weekly.1   824M      -   161G  -
ps1/mboxes@weekly.0  2,60G      -   247G  -
ps1/mboxes@daily.4    239M      -   285G  -
ps1/mboxes@daily.3    146M      -   286G  -
ps1/mboxes@daily.2    151M      -   286G  -
ps1/mboxes@daily.1   15,9M      -   286G  -
ps1/mboxes@hourly.5  6,49M      -   286G  -
ps1/mboxes@hourly.4  5,43M      -   286G  -
ps1/mboxes@hourly.3  5,80M      -   286G  -
ps1/mboxes@daily.0   7,84M      -   286G  -
ps1/mboxes@hourly.2  28,7M      -   286G  -
ps1/mboxes@hourly.1  65,1M      -   286G  -
ps1/mboxes@hourly.0  52,8M      -   287G  -

Backup host:

NAME                                       USED  AVAIL  REFER  MOUNTPOINT
as0/compointbck/mboxes@weekly.2            504M      -   131G  -
as0/compointbck/mboxes@weekly.1            695M      -   133G  -
as0/compointbck/mboxes@weekly.0           2,06G      -   202G  -
as0/compointbck/mboxes@daily.2             179M      -   233G  -
as0/compointbck/mboxes@daily.1             124M      -   233G  -
as0/compointbck/mboxes@daily.0            86,1M      -   233G  -
as0/compointbck/mboxes@hourly.0               0      -   234G  -

Command and output:
compoint:/ws # zxfer -dFkP -v -o compression=lz4 -T backuper@arc -N ps1/mboxes as0/compointbck

Writing backup info to location /as0/compointbck/.zxfer_backup_info.mboxes

Command duration is about 1 second. Nothing happens.

I don't know why, no output and no log message on either hosts.