Bitcoin on BLAKE2b — the chain the exchanges trade as XBT — did something this month that the old chain never had the stomach for. It locked the miners up. Since block 973,440, around September 22, newly mined coins cannot be spent for 45 days: a 6,480-block maturity on coinbase outputs, enforced by Knots 29.4.2 as a consensus rule, not a request. A de-serialized attempt to spend fails at the protocol level. Luke Dashjr calls it the first of three steps that could end with rewards withheld from blocks mined by non-miners.

Here is why the chain needed it, with numbers instead of vibes. The coin spiked to $1,799 in early September and fell some 84 percent below that high within days, as Bitcoin.com News reported — rented hashpower chasing the block subsidy, dumping the subsidy, and leaving true holders holding. A nine-week-old chain cannot survive being strip-mined by mercenaries. The lockup ends the mercenary’s exit: mine to dump, and you wait 45 days to sell into a crowd of people also waiting 45 days. Mine to build, and the lockup costs you nothing — it protects you from your neighbor’s exit.

The exchanges are behaving better than their reputation. NonKYC and SafeTrade kept deposits and withdrawals flowing for pre-lockup coins, per the BT Miners status check. Neoxa, which lists the coin as XBT, now publishes a proof of reserves read live off public block explorers — 6,081 XBT in a cold wallet you can verify address by address, on a page that invites you not to trust it. The biggest exchange on the dominant chain could never let that one sit on the mantel.

The tape this morning: Bitcoin itself at about $83,600, and XBT printing $345.87 on Neoxa against roughly $158,000 in 24-hour volume — back up from the $303 bottom of last week. The sellers who panic-sell a young chain are the ones who just got locked, and they are leaving. The community fills the space they vacate; this week’s refrain from the node runners on nostr tells you the mood: Blake2b mining is decentralized, the runners are relentless under attack, and everything Bitcoin spent years debating — spam, bad actors, money versus smart-coin — the BIP-110 community settled by consensus and moved on. One decentralization note to watch: AlphaPool crept toward half of the network’s hashrate mid-September and has promised a 30 percent cap. Keep the promise. We are counting.

A 45-day lockup is not a punishment. It is a filter. A young chain gets to pick its holders instead of having the market pick them for it, and this one is picking people who stay. Let the coin be held, not flipped.