This is the converse problem to https://vyos.dev/T7994: normalization of the config bind mount in https://vyos.dev/T7836 means that when searching for previous installations one searches in {mount_path}/opt/vyatta/etc/config. However, when searching for previous installations that were themselves created with the legacy bind mount (<= 1.4.4), the config.boot file resident there is not the saved version, but rather the baseline created by the original installation. One must therefore search both the legacy path {mount_path}/config as well as the normalized path. This is well defined, as the legacy path only exists in the case of legacy bind mount.

Note that this is not an issue for upgrades using add system image.