Good news, that it's doable by ADB.

Anyway here is an output of sudo system-image-cli -v:

phablet@ubuntu-phablet:~$ sudo system-image-cli -v
[sudo] password for phablet:
[systemimage] Apr 13 09:42:37 2016 (4190) running state machine
[ubuntu-touch/stable/meizu.en/arale]
[systemimage] Apr 13 09:42:37 2016 (4190) Looking for blacklist:
https://system-image.ubuntu.com/gpg/blacklist.tar.xz
[systemimage] Apr 13 09:42:37 2016 (4190) [0xb5826290] Requesting group
download:                        
       https://system-image.ubuntu.com/gpg/blacklist.tar.xz ->
/var/lib/system-image/keyring.tar.xz      
       https://system-image.ubuntu.com/gpg/blacklist.tar.xz.asc ->
/var/lib/system-image/keyring.tar.xz.asc                                    

[systemimage] Apr 13 09:42:37 2016 (4190) Allow GSM? No               
[systemimage] Apr 13 09:42:37 2016 (4190)
[/com/canonical/applications/download/com_2eubuntu_2eterminal_5fterminal_5f0_2e7_2e190/883872ab0c7f4425b4764db9eda977a2]
Running group download reactor
[systemimage] Apr 13 09:42:37 2016 (4190) self: <UDMDownloadManager at
0xb5826290>, self._iface: <Interface <ProxyObject wrapping
<dbus._dbus.SystemBus (system) at 0xb604c2d0> :1.135
/com/canonical/applications/download/com_2eubuntu_2eterminal_5fterminal_5f0_2e7_2e190/883872ab0c7f4425b4764db9eda977a2
at 0xb5826530> implementing 'com.canonical.applications.GroupDownload' at
0xb58262f0>
[systemimage] Apr 13 09:42:37 2016 (4190)
[/com/canonical/applications/download/com_2eubuntu_2eterminal_5fterminal_5f0_2e7_2e190/883872ab0c7f4425b4764db9eda977a2]
Group download reactor done
[systemimage] Apr 13 09:42:37 2016 (4190) uncaught exception in state
machine
Traceback (most recent call last):
 File "/usr/lib/python3/dist-packages/systemimage/state.py", line 133, in
__next__
   step()
 File "/usr/lib/python3/dist-packages/systemimage/state.py", line 219, in
_get_blacklist_1
   get_keyring('blacklist', url, 'image-master')
 File "/usr/lib/python3/dist-packages/systemimage/keyring.py", line 107,
in get_keyring
   (ascxz_src, ascxz_dst),
 File "/usr/lib/python3/dist-packages/systemimage/download.py", line 209,
in get_files
   self._get_files(records, pausable, signal_started)
 File "/usr/lib/python3/dist-packages/systemimage/udm.py", line 189, in
_get_files
   missing, local_paths))
AssertionError: Missing destination files:
['/var/lib/system-image/keyring.tar.xz',
'/var/lib/system-image/keyring.tar.xz.asc']
local_paths: [dbus.String('/tmp/blacklist (2).tar.xz'),
dbus.String('/tmp/blacklist (2).tar.xz.asc')]
Exception occurred during update; see log file for details
[systemimage] Apr 13 09:42:37 2016 (4190) system-image-cli exception
Traceback (most recent call last):
 File "/usr/lib/python3/dist-packages/systemimage/main.py", line 402, in
main
   list(state)
 File "/usr/lib/python3/dist-packages/systemimage/state.py", line 133, in
__next__
   step()
 File "/usr/lib/python3/dist-packages/systemimage/state.py", line 219, in
_get_blacklist_1
   get_keyring('blacklist', url, 'image-master')
 File "/usr/lib/python3/dist-packages/systemimage/keyring.py", line 107,
in get_keyring
   (ascxz_src, ascxz_dst),
 File "/usr/lib/python3/dist-packages/systemimage/download.py", line 209,
in get_files
   self._get_files(records, pausable, signal_started)
 File "/usr/lib/python3/dist-packages/systemimage/udm.py", line 189, in
_get_files
   missing, local_paths))
AssertionError: Missing destination files:
['/var/lib/system-image/keyring.tar.xz',
'/var/lib/system-image/keyring.tar.xz.asc']
local_paths: [dbus.String('/tmp/blacklist (2).tar.xz'),
dbus.String('/tmp/blacklist (2).tar.xz.asc')]
[systemimage] Apr 13 09:42:37 2016 (4190) state machine finished
phablet@ubuntu-phablet:~$