After several unsuccessful tries I have installed TWRP. Wiped the device. Then installed "recovery-turbo" again.
At the end I have installed RC channel with this command:
$ sudo ubuntu-device-flash --server=http://system-image.ubports.com touch --device=turbo --channel=15.04/rc
2017/12/07 13:35:44 Device is |turbo|
2017/12/07 13:35:44 Flashing version 12 from 15.04/rc channel and server http://system-image.ubports.com to device turbo
2017/12/07 13:35:45 Start pushing /home/andrzej/.cache/ubuntuimages/gpg/image-signing.tar.xz to device
2017/12/07 13:35:47 Start pushing /home/andrzej/.cache/ubuntuimages/pool/device-60f53a5768e9340729d3a5ef9263bd3a9726792e7d0dbf830e5b124938dd419a.tar.xz to device
2017/12/07 13:35:47 Start pushing /home/andrzej/.cache/ubuntuimages/pool/keyring-4c4e7ef380ebcfa2c31084efa199138e93bfed8fc58aa3eb06bdf75a78af9b57.tar.xz to device
2017/12/07 13:35:47 Start pushing /home/andrzej/.cache/ubuntuimages/ubports-touch/15.04/rc/turbo/version-12.tar.xz to device
2017/12/07 13:35:47 Start pushing /home/andrzej/.cache/ubuntuimages/gpg/image-master.tar.xz to device
2017/12/07 13:35:47 Start pushing /home/andrzej/.cache/ubuntuimages/pool/ubports-ab3bba2c6973569f7df80a7d9fe67bccbeec8edc58cf34e8c4a04f27293837b4.tar.xz to device
2017/12/07 13:35:48 Done pushing /home/andrzej/.cache/ubuntuimages/gpg/image-signing.tar.xz to device
2017/12/07 13:35:48 Done pushing /home/andrzej/.cache/ubuntuimages/pool/keyring-4c4e7ef380ebcfa2c31084efa199138e93bfed8fc58aa3eb06bdf75a78af9b57.tar.xz to device
2017/12/07 13:35:48 Done pushing /home/andrzej/.cache/ubuntuimages/ubports-touch/15.04/rc/turbo/version-12.tar.xz to device
2017/12/07 13:35:48 Done pushing /home/andrzej/.cache/ubuntuimages/gpg/image-master.tar.xz to device
2017/12/07 13:36:10 Done pushing /home/andrzej/.cache/ubuntuimages/pool/device-60f53a5768e9340729d3a5ef9263bd3a9726792e7d0dbf830e5b124938dd419a.tar.xz to device
2017/12/07 13:36:45 Done pushing /home/andrzej/.cache/ubuntuimages/pool/ubports-ab3bba2c6973569f7df80a7d9fe67bccbeec8edc58cf34e8c4a04f27293837b4.tar.xz to device
2017/12/07 13:36:45 Created ubuntu_command: /home/andrzej/.cache/ubuntuimages/ubuntu_commands881164790
2017/12/07 13:36:46 Rebooting into recovery to flash
I have read on another topic that I should not use "" --bootstrap " option. Anybody knows why? Why it is there in the documentation?
(sorry for answering myself, but I think somebody else might learn from my experience while installing UBPorts on Meizu Pro 5)
