dovecot - Jul 2020 - BUG report: dbox movealt doesn't move reverse (to default location)

Hi,

Here is the problem that occured: 
#sudo doveadm -D altmove -u vv at vito.pp.ua all 
works properly and moves all storage to alt dir.
However, to move it back to default storage I add '-r' by manual:
#sudo doveadm -D altmove -u vv at vito.pp.ua -r all
That seems behave like the original command ignoring '-r'.


my dovecot conf:

# 2.3.4.1 (f79e8e7e4): /etc/dovecot/dovecot.conf
# Pigeonhole version 0.5.4 ()
# OS: Linux 4.19.0-9-amd64 x86_64 Debian 10.4 
# Hostname: qemu7.internetguru.ca
auth_mechanisms = plain login
disable_plaintext_auth = no
imapc_features = rfc822.size fetch-headers
imapc_host = imap.gmail.com
imapc_port = 993
imapc_ssl = imaps
imapc_user = %u
listen = *,[::]
log_timestamp = "%Y-%m-%d %H:%M:%S "
mail_attachment_dir = /wd640/mdbox-att/%d/%n
mail_max_userip_connections = 100
mail_prefetch_count = 20
mail_privileged_group = vmail
passdb {
  args = /etc/dovecot/dovecot-sql.conf
  driver = sql
}
plugin {
  quota = dict:user::file:/var/vmail/%d/%n/.quotausage
  sieve = /var/vmail/%d/%n/.sieve
  sieve_max_redirects = 25
}
protocols = imap pop3
service auth {
  unix_listener /var/spool/postfix/private/auth {
    group = postfix
    mode = 0660
    user = postfix
  }
  unix_listener auth-userdb {
    group = vmail
    mode = 0600
    user = vmail
  }
  user = root
}
service imap-login {
  client_limit = 1000
  process_limit = 512
}

service lmtp {
  unix_listener /var/spool/postfix/private/dovecot-lmtp {
    group = postfix
    mode = 0600
    user = postfix
  }
}
service stats {
  unix_listener stats-reader {
    group = vmail
    mode = 0660
    user = vmail
  }
  unix_listener stats-writer {
    group = vmail
    mode = 0660
    user = vmail
  }
}
ssl_cert = </etc/postfix/smtpd.cert
ssl_client_ca_dir = /etc/ssl/certs
ssl_dh = # hidden, use -P to show it
ssl_key = # hidden, use -P to show it
userdb {
  driver = prefetch
}
userdb {
  args = /etc/dovecot/dovecot-sql.conf
  driver = sql
}
protocol imap {
  mail_plugins = quota imap_quota
}
protocol pop3 {
  mail_plugins = quota
  pop3_uidl_format = %08Xu%08Xv
}
protocol lda {
  mail_plugins = sieve quota
  postmaster_address = postmaster at some.ca
}
protocol lmtp {
  mail_plugins = quota sieve
  postmaster_address = postmaster at some.ca
}


I am using debian 10.

P.S. I have not found much information about dbox attachments commands.
Seems none needs them.