I just tried to install IodéOS like described in the title, following the instructions on the homepage, using a PC with Linux Mint.
I ran into the “fastboot too old” error message, so I deleted the version check as a random internet find did recomend. The installation afterwards seemed to be fine, but went into bootloop, interchanging between the “bootloader unlocked” screen and the Fairphone logo. I tried again, and messed around a bit, but it to no avail.
I am back to Lineage for now, having a functioning phone, but am eager to switch to IodeOS. Are there any more detailed instructions for the FP3, perhaps with more checks to ensure a smooth installation, that I can use? Especially about the a/b-partition which I have only a very vague idea about, because it seemed to switch between these, if I understood the output of fastboot correctly. Relocking the Bootlocker is not important for me. I would sideload IodeOS also, if this is a more stable way.
Thank you very much!