What happens to Kaspa nodes that aren't upgraded before Toccata activates?

Any Kaspa node still running software older than v2.0.0 will be automatically disconnected from the network 24 hours before Toccata activates. Because Toccata is a hard fork, the pre-upgrade and post-upgrade software speak different protocol dialects and cannot stay on the same network together. There is no grace period after the cutoff — unupgraded nodes are simply dropped. For anyone running a node, this means upgrading to v2.0.0 or later before the activation deadline is not optional; missing the window means being offline until the update is applied.