@hans1977se alright, decompressing the version1.tar.xz yields these files:
720.0 # tree
.
|-- system
| `-- etc
| |-- system-image
| | |-- channel.ini
| | `-- config.d
| | |-- 00_default.ini -> ../client.ini
| | `-- 01_channel.ini -> ../channel.ini
| `-- ubuntu-build
`-- version-1.tar.xz
as for the keyring file:
729.0 # tree
.
|-- device-60f53a5768e9340729d3a5ef9263bd3a9726792e7d0dbf830e5b124938dd419a.tar.xz
|-- device-60f53a5768e9340729d3a5ef9263bd3a9726792e7d0dbf830e5b124938dd419a.tar.xz.asc
|-- keyring-4c4e7ef380ebcfa2c31084efa199138e93bfed8fc58aa3eb06bdf75a78af9b57.tar.xz
|-- keyring-4c4e7ef380ebcfa2c31084efa199138e93bfed8fc58aa3eb06bdf75a78af9b57.tar.xz.asc
|-- system
| `-- usr
| `-- share
| `-- system-image
| |-- archive-master.tar.xz
| `-- archive-master.tar.xz.asc
|-- ubports-d50c18b27590af5734a826c4f7857d8909b0e0f902d21af142a780620c8eb58b.tar.xz
`-- ubports-d50c18b27590af5734a826c4f7857d8909b0e0f902d21af142a780620c8eb58b.tar.xz.asc
In any case couldn't it be possible to manually download the kernel files and flash them like I did originally for the canonical ubuntu-touch? I used the method from this link: https://askubuntu.com/questions/767323/how-to-install-ubuntu-on-meizu-pro-5-that-was-originally-with-android
I would need a kernel-OTA-15.zip (with boot.img, dtb, logo.bin, ldfw), ubuntu*.tar.xz, device*.tar.xz, custom*.tar.xz, version*.tar.xz. Basically doing whatever worked in the past with canonical...
Anyway, there seems to be nothing wrong with my partition table as shown by the command below...
746.0 # adb shell sgdisk --print /dev/block/sda | grep -v GUID
Disk /dev/block/sda: 7633920 sectors, 29.1 GiB
Logical sector size: 4096 bytes
Partition table holds up to 128 entries
First usable sector is 6, last usable sector is 7633914
Partitions will be aligned on 64-sector boundaries
Total free space is 11386 sectors (44.5 MiB)
Number Start (sector) End (sector) Size Code Name
1 1024 1279 1024.0 KiB 0700 private
2 1280 1343 256.0 KiB 0700 proinfo
3 1344 1407 256.0 KiB 0700 misc
21 2048 3071 4.0 MiB 0700 param
22 3072 5119 8.0 MiB 0700 efs
23 5120 5631 2.0 MiB 0700 pnv
24 5632 6655 4.0 MiB 0700 ldfw
25 6656 7679 4.0 MiB 0700 dtb
26 7680 13823 24.0 MiB 0700 bootimg
27 13824 22015 32.0 MiB 0700 recovery
28 22016 30207 32.0 MiB 0700 bootlogo
29 30208 35327 20.0 MiB 0700 rstinfo
30 35328 40447 20.0 MiB 0700 mnv
31 40448 45567 20.0 MiB 0700 reserved1
32 45568 50687 20.0 MiB 0700 reserved2
33 50688 55807 20.0 MiB 0700 reserved3
41 65536 720895 2.5 GiB 0700 system
42 720896 851967 512.0 MiB 0700 custom
43 851968 983039 512.0 MiB 0700 cache
44 983040 7633914 25.4 GiB 0700 userdata