@marcoi I don't have enough context to reply. You should open a new thread to discuss it, with details about your needs (always better to explain the needs before the technical solution).
Ah indeed, labels are honored even in the case of a warm migration.
We used it ourselves when we migrated from Intel to AMD CPUs, it was really the best compromise betweeen live and cold (especially when you change the CPU vendor).
Glad to see it's helping many people and companies now
So just for my understanding. For restoring a metadata backup or maybe also other backups I need the correct XAPI version, but a XCP-ng user is not able to select/control the needed version? Sounds lika a chicken-egg-problem…
Is it not possible to have a new .iso-Image, whenever such updates are provided? It would be an easy way on case of new Installation.