---
name: avax-upgrades
description: Verify Avalanche ACP activation, node releases and EVM feature support separately for each target network.
---

# Upgrades & stale assumptions

Source review: 2026-09-06. Recheck network-dependent facts before use.

1. Locate the ACP or EIP claim in official documentation and the corresponding implementation release. Record whether it is proposed, implemented, activated on Fuji or activated on mainnet. A proposal's existence does not establish deployment.
2. Check the network's activation schedule and running software compatibility. Read chain-specific release notes before using a new transaction type, RPC namespace, precompile, opcode or staking rule.
3. Compare tutorial settings with the target network's current behavior. Preserve an explicit EVM compiler target; a fork name supported on Ethereum is not automatic evidence of Avalanche support.
4. For an L1, inspect its own VM/genesis/upgrade configuration. Primary Network activation dates are not a substitute for that chain's rules.
5. Capture a dated decision record with the verified source and the feature-dependent tests that passed. If official pages disagree, prefer release/activation evidence and describe the unresolved conflict.

## Dated example of why this matters

On 2026-09-06, official Helicon documentation lists Fuji activation on July 28, 2026 and mainnet activation as not yet scheduled. The linked AvalancheGo v1.15.0-fuji release is Fuji-only. Re-read both before using this observation later.

Do not apply Helicon's gas, execution or staking changes universally from that testnet status. A successful Fuji test is not proof of mainnet feature support.

As of the same review, ACP-209 (EIP-7702-style account delegation) is marked Proposed. Verify an activation release before enabling that feature; Ethereum support alone is insufficient.

## Primary sources

- [Helicon activation status](https://build.avax.network/docs/primary-network/helicon-upgrade)
- [AvalancheGo Fuji release](https://github.com/ava-labs/avalanchego/releases/tag/v1.15.0-fuji)
- [Avalanche Community Proposals](https://build.avax.network/docs/acps)

- [ACP-209 status](https://build.avax.network/docs/acps/209-eip7702-style-account-abstraction)

## Preserve a dated feature decision

The 2026-09-06 primary-source review finds Helicon active on Fuji from July28,2026, with mainnet activation unscheduled and AvalancheGo v1.15.0-fuji linked for testnet. Re-read the exact official page/release before using these facts later.

ACP209 EIP7702-style delegation remains Proposed and is not one of the six Helicon ACPs. Ethereum Pectra, compiler support or Fuji Helicon does not establish C-Chain delegation. The executable `examples/standards/feature-policy.mjs` deliberately disables delegation until target activation is verified.

Run `node --test examples/standards/standards.test.mjs` and read its pinned primary-source manifest. These prove conservative feature gating, not a successful 7702 transaction. An unavailable RPC method alone is insufficient absence evidence.

For an L1 inspect its own VM, genesis, precompile permissions and upgrade schedule. A state fork may enable instructions absent on the target network. Deliver feature/status, implementation/release, activation evidence, target/compiler configuration and actual compatibility test.

Primary references: [Helicon](https://build.avax.network/docs/primary-network/helicon-upgrade), [Fuji release](https://github.com/ava-labs/avalanchego/releases/tag/v1.15.0-fuji), [ACP209](https://build.avax.network/docs/acps/209-eip7702-style-account-abstraction).