> ## Documentation Index > Fetch the complete documentation index at: https://docs.optimism.io/llms.txt > Use this file to discover all available pages before exploring further. # Notice archive > Completed network notices for OP Stack operators, newest first, with the date each change took effect. Every notice on this page is finished: the upgrade activated, the deprecation took effect, or the exercise completed. They are kept because live pages link into them and because they record what operators were asked to do at the time. Their URLs are permanent. For notices that still need action, see [Notices](/notices). For the permanent record of a network upgrade (activation timestamps, governing specification, and minimum component versions), see the [hardfork registry](/op-stack/protocol/network-upgrades); contract-only upgrades are in the registry's [contract upgrades table](/op-stack/protocol/network-upgrades#contract-upgrades). ## Archived notices The **Effective** column is the date the change took effect: mainnet hardfork activation, the end-of-support date, the mainnet execution date of a contract upgrade, or the start of a time-boxed experiment. A few notices never recorded one. Those rows say so and are placed at their nearest known point in the sequence rather than given a date they cannot support. | Effective | Notice | What it covered | | ---------- | ---------------------------------------------------------------------------------------------------------- | ------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------ | | 2026-07-08 | [Upgrade 19: Karst hard fork](/notices/archive/upgrade-19) | Karst: the L2 Contract Manager (L2CM), `CANNON_KONA` promoted to the respected game type, a subset of Osaka EIPs on L2, and a preemptive BN256 pairing input-size reduction. | | 2026-06-26 | [Deprecation of Req/Res CL P2P sync](/notices/archive/req-resp-cl-sync-deprecation) | Retirement of the `op-node` request-response consensus-layer P2P sync client in favor of syncing through the execution client. Removed in `op-node/v1.19.1`. | | 2026-05-31 | [End of Support for op-geth and op-program](/notices/archive/op-geth-deprecation) | End of support for op-geth and op-program, neither of which supports Karst. Migrate execution to op-reth and fault proofs to kona-client. | | 2026-05-26 | [Stake-based priority ordering on OP Mainnet](/notices/archive/stake-based-priority-ordering) | A time-boxed OP Mainnet experiment giving stakers in the `PolicyEngineStaking` contract priority in transaction ordering, capped at four weeks. | | Not dated | [Deprecation of op-deployer upgrade and manage commands](/notices/archive/op-deployer-upgrade-deprecation) | `op-deployer manage` retired, and `op-deployer upgrade` capped at `op-contracts/v5.0.0`. L1 contract upgrades beyond that use superchain-ops or OPCM directly. Postdates `op-contracts/v6.0.0`. | | Not dated | [Upgrade 18: Cannon + Kona and Custom Gas Token v2](/notices/archive/upgrade-18) | Contract-only upgrade adding the `CANNON_KONA` (8) game type alongside `CANNON` (0), Custom Gas Token v2, and the creator-pattern dispute game refactor. Shipped in [`op-contracts/v6.0.0`](/releases/op-contracts) (released 2026-03-16). | | 2025-12-03 | [Fusaka upgrade notice](/notices/archive/fusaka-notice) | Readiness work so OP Stack chains keep deriving from an L1 that has activated Fusaka and its blob parameter-only forks. Not Fusaka adoption on L2. | | 2025-12-02 | [Upgrade 17: Jovian hard fork](/notices/archive/upgrade-17) | Jovian: a configurable minimum base fee, the data-availability footprint block limit, and Cannon support for Go 1.24. | | 2025-10-02 | [Upgrade 16a](/notices/archive/upgrade-16a) | Maintenance contract upgrade superseding Upgrade 16: removes the unused interop withdrawal-proving code and adds `SystemConfig` feature toggles. | | 2025-07-24 | [Upgrade 16: preparing for interop](/notices/archive/upgrade-16) | Contract upgrade making `OptimismPortal` interop-ready, meeting updated Stage 1 requirements, adding Go 1.23 support in Cannon, and raising `MAX_GAS_LIMIT` to 500M. Invalidated existing withdrawal proofs. | | 2025-05-14 | [Superchain withdrawal pause test](/notices/archive/superchain-withdrawal-pause-test) | A scheduled exercise of the Superchain-wide `pause` and `unpause` incident-response path. No user or operator action was required. | | 2025-05-09 | [Upgrade 15: Isthmus hard fork](/notices/archive/upgrade-15) | Isthmus: Prague features on the OP Stack, the L2 withdrawals root in the block header, and the operator fee. | | Not dated | [Upgrade 14: MT-Cannon and Isthmus L1 contracts](/notices/archive/upgrade-14) | Contract upgrade shipping multithreaded 64-bit Cannon (MT-Cannon) and the Isthmus L1 contracts. Shipped in [`op-contracts/v3.0.0`](/releases/op-contracts) (released 2025-05-08); the notice's own mainnet date was an estimate. | | Not dated | [L1 Pectra user fees and chain profitability](/notices/archive/pectra-fees) | How the [EIP-7623](https://eips.ethereum.org/EIPS/eip-7623) gas repricing at L1 Pectra affected chains still posting data as calldata rather than blobs, and which Ecotone scalars to check. | | 2025-04-02 | [Upgrade 13: OPCM and incident response](/notices/archive/upgrade-13) | Contract upgrade introducing the OP Contracts Manager (OPCM), fault-proof incident response improvements, and the `DeputyPauseModule`. | | 2025-03-20 | [Superchain testnets' blob fee bug](/notices/archive/blob-fee-bug) | A testnet-only blob base fee miscalculation that overcharged L1 fees, and the hardfork activation that fixed it. Mainnet chains were never affected. | | Not dated | [Preparing for Pectra breaking changes](/notices/archive/pectra-changes) | Breaking changes for chain and node operators when Pectra activated on L1. The page carries only tentative L1 slot times that were later superseded; it was last revised 2025-03-11. | | 2025-01-09 | [Preparing for Holocene breaking changes](/notices/archive/holocene-changes) | Holocene: stricter block derivation, EIP-1559 parameters made configurable through `SystemConfig`, and the MIPS contract upgrade. |