Filecoin Solstice: Lotus v1.37.0 is mandatory before epoch 6470279

Protocol upgrades do not care about your weekend plans. Lotus v1.37.0 is the Mainnet build operators must be on before Solstice lands.

On 6 October 2026, the filecoin-project/lotus repository published v1.37.0—described as the stable, mandatory release delivering Filecoin network version 29, codenamed “Solstice.” The Mainnet upgrade epoch is set to 6470279, corresponding to 2026-10-19T12:59:30Z (afternoon in Europe/London once converted from that UTC stamp). [1]

This explainer is drawn from the official GitHub release notes, not exchange marketing or price commentary. Filed under Web 3 (DePIN storage protocol), not Bitcoin.

What Solstice changes (FIP-0118)

Network version 29 implements FIP-0118 (Solstice): deprecate Fil+ and fund services via a block-reward split, shipping built-in actors v19.0.1. From nv29, every new sector receives maximum quality-adjusted (QA) power regardless of content, and the verified registry and DataCap actors are frozen—DataCap and verified-registry writes are refused. [1]

Practical CLI and pipeline fallout called out in the notes includes: lotus filplus datacap commands retire; lotus-miner sectors extend --drop-claims is rejected; --only-cc is removed in favour of --exclude; operators should use lotus-miner sectors upgrade-quality (with --sectors selection support) to raise legacy 1x-QA sectors. PreCommitSectorBatch2 rejects non-empty deal_ids from nv29, and the sealing pipeline refuses such queued sectors. [1]

Operator warnings that matter

All Lotus node and storage-provider operators on Mainnet must upgrade to v1.37.0 before epoch 6470279. The Solstice migration installs reward-actor bootstrap state from per-network parameters, resolving service-weight authority, service-rewards actor, and initial orchestrator to ID addresses against the state tree at the upgrade epoch. [1]

One pre-migration is scheduled 120 epochs before the upgrade. A mainnet benchmark cited in the notes (18 September 2026; ~64-thread AMD EPYC 7282, 503 GiB RAM, NVMe datastore) took about 64 seconds for pre-migration and ~63 seconds at the upgrade epoch while syncing, with peak daemon memory around 38 GiB—nodes on slower disks/CPUs or under heavier load should expect longer times. [1]

API notes: StateMinerInitialPledgeCollateral returns an error from nv29 because SectorPreCommitInfo no longer describes any part of the pledge; use StateMinerInitialPledgeForSector, passing full sector size as verified size. A new v2 StateRewardDistribution API covers block rewards, recipient earnings, payments, and tipset totals. F3 Prometheus metric names may change after an OpenTelemetry exporter bump (v0.50.0 → v0.68.0)—operators with f3_* dashboards should re-check names; core lotus_* metrics via OpenCensus are unchanged. [1]

What we don’t know

• How quickly the storage-provider fleet will actually upgrade before the epoch.
• Economic effects of freezing Fil+/DataCap writes beyond what FIP-0118 specifies.
• Any Mainnet incidents during the migration itself (this release predates the upgrade).
• Whether all miner tooling vendors have shipped compatible builds.

What this does not prove

A mandatory client release does not by itself prove smooth Mainnet migration, or that storage economics improve for every provider class after QA-power changes. It proves the Lotus maintainers have cut the Solstice build and set the epoch. [1]

The Bottom Line

Lotus v1.37.0 is the mandatory Solstice (nv29) Mainnet client: upgrade before epoch 6470279 on 19 October 2026 UTC, expect Fil+/DataCap write freezes, and plan migration time and dashboard metric renames. Engineering release notes—not a price story. Not investment advice.

Sources

1. filecoin-project/lotus GitHub releases — v1.37.0 — 6 October 2026 — https://github.com/filecoin-project/lotus/releases/tag/v1.37.0