About 12,226 ZEC will likely never move again. Zcash's NU7 network upgrade activates at block 3,543,405, which reports put around November 5 to 6, and drops the target block time from 75 seconds to 25, with the reward per block cut in proportion, according to TechFlow and CryptoTicker. It also ends support for the version 4 transaction format, the only route out of Sprout, the original shielded pool launched in October 2016. Once nodes reject v4 transfers, coins left in Sprout cannot be spent even by owners holding valid keys. TechFlow, citing CoinDesk, puts the stranded amount near 12,226 ZEC, about $16 million at roughly $1,300 a coin. Holders have been leaving: about 10,037 ZEC exited Sprout over the past week, including a net 9,094 ZEC on Sunday, before daily outflows fell to about 40 ZEC by Wednesday. ZIP 2003 reserves space for a possible future withdrawal path, though the specification warns the funds "will most likely never be extractable again." Balances on exchanges and on transparent addresses are unaffected. Miners and node operators need Zebra 7.0.0, since zcashd is no longer supported, and CryptoTicker reports transaction fees will split 60% to the reserve and 40% to miners.