November 21, 2022 at 11:05 PMA protocol update to implement smart contract upgradability and performance improvements will take effect on testnet on November 22, 2022.
New node software compliant with the protocol update is released for Linux, Windows, and MacOS here.
Node runners must upgrade their nodes before the new protocol takes effect. Old nodes will stop processing new blocks at that point.
For more details on the protocol update, see concordium-update-proposals.
The protocol update on testnet is in preparation of a similar protocol update on mainnet in December.