Gitlab Multi-Node setup upgradation query

Query - How does not upgrading some components of a multi-node setup affect the setup ?

Eg - I have created this Gitlab Setup (Multi-Node upto 2k users) 14.8.5 version and am trying to upgrade.

Will Gitlab break if I upgrade only the Rails node with the gitlab package and leave the Postgres, Redis, and Gitaly nodes without upgrading ?

If no, how many upgrades of the other components can I skip (Just upgrading the Rails node) without breaking the setup ?

Thanks