Zcash Hits NU7 Testnet Tomorrow: 25-Second Blocks, a Fee-Recycling Engine - and the $1,344 Line That Decides $1,600 or $1,271

Zcash's next network upgrade reaches its first live environment tomorrow. NU7 activates on the public testnet at block height 4,465,026, expected around Oct. 6, and the Zcash Foundation has shipped Zebra 7.0.0-rc.0 - the first release candidate for the upgrade - with node operators urged to be running it before activation.

The release candidate landed on Oct. 2 and is the point at which the upgrade stopped being a design document. NU7 is code-complete in Zebra, the Rust node implementation, and the testnet window is the first chance for operators to run the new consensus rules in public before the mainnet height is fixed.

What NU7 Actually Changes

NU7 is a hard fork with three moving parts. ZIP-218 cuts the target block spacing from 75 seconds to 25. Version 4 transactions are switched off. And the Network Sustainability Mechanism - ZIP-234 in its voted form plus ZIP-235 - is added to keep paying for network security once the block subsidy stops covering it.

The headline effect is confirmation speed. A Zcash user currently waits 75 seconds on average for a first confirmation, which the Foundation describes as a real obstacle at the point of sale, for exchange deposits and for cross-chain bridges. After NU7 that wait drops to 25 seconds, so the same number of confirmations accumulate in a third of the time.

The supply schedule is deliberately untouched. Because blocks arrive three times as often, the per-block subsidy is cut roughly threefold, which keeps the amount of ZEC issued per day unchanged and preserves the four-year halving rhythm against the 21 million cap. NU7 introduces no new transaction formats and, in the developers' own framing, is not meant to affect wallets materially.

A Fee Engine for the Post-2031 Network

The NSM is the part that outlives the price headlines. Under ZIP-235, 60% of each block's transaction fees are withdrawn from circulation and deposited in a reserve, while miners keep the remaining 40% - which keeps them motivated to include transactions. Under ZIP-237, every block then reissues a small, predictable slice of that reserve on top of its normal reward, as the upgrade alert sets out.

The practical timeline is long, and worth stating plainly: the coins held back are issued again from February 2031. What NU7 buys is predictability - a security budget that leans on fees rather than on a rising price, which is the part that matters most once the halving schedule grinds the subsidy down. The 21 million cap and the existing halvings both stay exactly where they are.

The community settled the direction before the code shipped. A coinholder vote that closed on Sept. 14 drew backing from 98.9% of participating ZEC for keeping the Bitcoin-style halvings alongside the faster blocks, and core developer Sean Bowe published the four-date timeline on the Zcash Community Forum on Sept. 17 after agreement across the Foundation, Tachyon, Valar, ZODL and SL.

Four Dates, One of Which Is Not Fixed

The checklist is short. Code complete by Sept. 30 - done. Testnet activation on Oct. 6 at height 4,465,026. The mainnet activation height gets set on Oct. 20, a week before the Zcash conference Zcon. Mainnet goes live on Nov. 5.

One caveat matters for anyone tracking this hour by hour: the official upgrade page still says the mainnet activation height has not been set. Network upgrades switch on at a block height rather than a clock time, so Oct. 20 is the day a target date becomes a number - and only then is Nov. 5 more than a plan.

"Zebra 7.0.0-rc.0 is here - NU7 arrives on Testnet. Blocks every 25 seconds instead of 75. Activates on Testnet at height 4,465,026 (~Oct 6). Testnet operators should upgrade before then." - Zcash Foundation, Oct. 2, 2026

Who Has to Do Something (Almost Nobody)

For holders the answer is nothing: no swap, no migration deadline, no address to send anything to. The people with work to do are the ones running infrastructure - full nodes, indexers and block explorers. A maintained wallet has been producing v5 transactions for years, so the only holder-side task is updating software old enough to still produce v4 transactions, and testing it on the testnet while a mistake costs nothing.

NU7 also adds per-block shielded limits: 330 Orchard or Ironwood operations, 300 Sapling inputs and outputs, a shared budget of 330 across pools, and no new Sprout JoinSplits. The purpose is to stop spam from filling shielded blocks. Upgrades also attract phishing, and the standard warning applies in full - there is no legitimate NU7 process that asks anyone to unlock a wallet or hand over a recovery phrase.

Where ZEC Sits Going Into the Testnet

The market has spent two weeks unwinding September's move. ZEC peaked at $1,698 on Sept. 26 and slid to $1,271.09 on Oct. 2, a 25% drawdown in six sessions. The last three sessions have printed higher lows at $1,283.17 and $1,303.00, and Sunday's candle broke a ceiling that had been stepping down since Sept. 30.

Oct. 4 traded as high as $1,368.09 - above the previous session's $1,334.79 high - and closed at $1,352.37, up 3.6%. That leaves the price sitting almost exactly on the 0.382 retracement of the August-to-September leg from $773.01 to $1,698.00, which comes in at $1,344.65. The 20-day moving average is at $1,463.74, still overhead.

The funding side has cooled with the price. Grayscale's Zcash ETF - the first US-listed spot ZEC vehicle, which began trading on Aug. 25 - recorded $93.56 million of net redemptions in the week ended Oct. 2, its first negative week since late August, after taking in $245.92 million during September. Net assets stood at $751.03 million on Oct. 2, and the trust completed a 3-for-1 forward share split on Sept. 30 without changing the value of anyone's position.

Size check: ZEC carries about $22.9 billion of market capitalisation at $1,351, ranking tenth among cryptocurrencies, on roughly $498 million of daily volume. It is up 32% over 30 days and down 14.9% over seven.

What Decides the Next Leg

The line is the 0.382 retrace. Holding $1,344 and reclaiming the $1,412 and $1,494 highs from Sept. 30 and Oct. 1 puts the $1,598-$1,650 shelf back in play and, above it, a retest of the $1,698 top. Losing $1,303 and then the $1,271 Oct. 2 low opens the 0.5 retrace at $1,235.51 and, below that, the 0.618 at $1,126.36.

Volatility is the other number to respect. The 14-day average true range is $123, or 9.1% of spot, so an ordinary day in this market covers the distance between those levels on its own. Price is also still trading below its 20-day average, which means the rebound has to prove itself rather than simply continue.

Two things are worth watching into Oct. 20. First, whether the testnet runs clean at 25-second spacing, because that is the evidence the mainnet decision rests on. Second, whether ETF flows turn positive again, since September's bid came through that channel and the final three sessions of last week handed $85.4 million back. NU7 is a protocol event, not a payout - it moves no coins for ordinary holders - and the level that decides the next leg is the one ZEC is standing on right now.