I am not sure what do you mean by rescue image. It might be just that misunderstanding but just to be sure:
@peci1 it should have been schnapps import -f to import it as factory image. That is OS (medkit) used when factory reset is performed.
There is also rescue image. I think that @mcr314 might be talking about that. It is stored in NOR and is used to perform medkit operations and other rescue modes. Mox was indeed shipped with older (but for Mox stable) version of rescue image. In development for Omnia 2019 we discovered bug in it that causes system to not read boot arguments correctly and that way only way to use rescue is trough button. This was fixed in Omnia but new version wasn’t mark as stable for Mox as we have not tested it well yet. You can use nor-update to update content of NOR. In default it just uses stable versions. You can use -d to flash development one (that is latest build) but with that you are on your own and you should be sure that you can perform serial boot to rescue your Mox if anything goes wrong as development builds are not regularly tested. (Documentation is not live yet but was merged already https://gitlab.labs.nic.cz/turris/user-docs/-/commit/8ffd55c9195a984acf8a021a9fc9f27c5d3ef3c8)