BlockBeats report: On November 5, Zcash plans to implement the NU7 network upgrade on Thursday evening, at which point it will cease accepting Version 4 transactions—the only format currently capable of transferring funds out of the Sprout privacy pool. After the upgrade, any ZEC remaining in the Sprout pool will become unusable, even if holders possess valid private keys.

As of Thursday morning, approximately 12,226 ZEC remained in the Sprout pool, a decrease of about 10,037 ZEC from the roughly 22,263 ZEC available a week earlier. Of this, approximately 9,094 ZEC were withdrawn on Sunday, while only about 40 ZEC were withdrawn on Wednesday. At approximately $1,300 per ZEC, the remaining assets are valued at around $16 million. Sprout was Zcash’s first privacy pool, launched in October 2016, and has since been superseded by newer privacy pools.

This upgrade is expected to activate at block height 3,543,405, which, based on the current block production rate, is approximately 9:30 PM Eastern Time on Thursday. However, the actual time depends on miner block production speed and may be delayed into Friday during Asian hours. The ZIP 2003 specification preserves the possibility of restoring access to Sprout funds in the future, but also warns that these assets may never be usable again. Additionally, NU7 reduces the target block interval from 75 seconds to 25 seconds to accelerate transaction confirmations.