It's important to not allow your signers to fall behind too far.
Is verifying and upgrading signer firmware relevant if you backup the seed phrases and the metadata?
Discussion
Hm, why’s that though? Aren’t the signing devices storing keys derived from the seed phrases of the multisig? And if you have the essential metadata for the multisig, you could theoretically only store the essential metadata and the n number of seed phrases and in the future get new signing devices with keys generated from imputing the seed phrases to then sign a multisig transaction.
Unless I’m misunderstanding something?