We are upgrading our Zcash Testnet infrastructure to Zebra 7.0.0-rc.0 on 2026-10-05. This release candidate activates the NU7 network upgrade on Testnet at height 4,465,026, introducing ZIP 259 branch IDs, ZIP 218 difficulty and action-limit changes, and the ZIP 237 NSM value pool. The upgrade includes significant RPC behavior changes affecting miners and applications. Brief interruptions to RPC availability may occur on that date.
RPC Changes: - getblocktemplate — The advertised mutable list now contains only time; transactions and prevblock have been removed. Miners must request a new template rather than modifying transactions or parent block independently. The coinbaserxn.fee field now reports negative collected miner fees (excluding NSM contribution from NU7 onward), and the depends array reports each parent transaction once using 1-based position. - getnetworksolps — Now returns an RPC error instead of panicking when the estimated solution rate exceeds its supported integer range. The method selects the 17- or 102-block averaging window for nonpositive block counts using the effective height in the same state snapshot, including requests above the current tip. - getstandardfee — On Mainnet reports 5000 zatoshis per logical action until height 3,590,000, then 1000 from that height onward. Test networks report 1000 at every height. getblocksubsidy — Now rejects heights above the consensus limit before reading state or computing subsidy.