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Co-authored-by: str4d <thestr4d@gmail.com>

doc/release-notes.md

@@ -13,7 +13,8 @@ RPC Changes
   - A new `end_of_service` object that contains both the block height for
     end-of-service and the estimated time that the end-of-service halt is
     expected to occur. Note that this height is just an approximation and
-    should not be relied upon due to the variability in block times. The
+    will change over time as the end-of-service block height approaches,
+    due to the variability in block times. The
     `end_of_service` object is intended to replace the `deprecationheight`
     field; see the [Deprecations](#deprecations) section for additional detail.
   - This RPC method was previously only available for mainnet nodes; it is now

qa/rpc-tests/wallet_deprecation.py

@@ -91,6 +91,9 @@ class WalletDeprecationTest(BitcoinTestFramework):
         default_enabled = dep_info['deprecated_features']
         default_disabled = dep_info['disabled_features']
 
+        for function in TESTABLE_FEATURES:
+            assert(function in default_enabled or function in default_disabled)
+
         # RPC methods that are deprecated but enabled by default should succeed
         for function in default_enabled:
             if function in TESTABLE_FEATURES:

src/deprecation.cpp

@@ -28,6 +28,12 @@ bool fEnableWalletTxVJoinSplit = true;
 
 static const std::string CLIENT_VERSION_STR = FormatVersion(CLIENT_VERSION);
 
+int64_t EstimatedNodeDeprecationTime(const CClock& clock, int nHeight) {
+    auto blocksToDeprecation = DEPRECATION_HEIGHT - nHeight;
+
+    return clock.GetTime() + (blocksToDeprecation * Consensus::POST_BLOSSOM_POW_TARGET_SPACING);
+}
+
 void EnforceNodeDeprecation(int nHeight, bool forceLogging, bool fThread) {
 
     // Do not enforce deprecation in regtest or on testnet

src/deprecation.h

@@ -6,6 +6,8 @@
 #define ZCASH_DEPRECATION_H
 
 #include "consensus/params.h"
+#include "util/time.h"
+
 // Deprecation policy:
 // Per https://zips.z.cash/zip-0200
 // Shut down nodes running this version of code, 16 weeks' worth of blocks after the estimated
@@ -62,6 +64,12 @@ extern bool fEnableAddrTypeField;
 extern bool fEnableWalletTxVJoinSplit;
 #endif
 
+/**
+ * Returns the estimated time, in seconds since the epoch, at which deprecation
+ * enforcement will take effect for this node.
+ */
+int64_t EstimatedNodeDeprecationTime(const CClock& clock, int nHeight);
+
 /**
  * Checks whether the node is deprecated based on the current block height, and
  * shuts down the node with an error if so (and deprecation is not disabled for

src/rpc/net.cpp

@@ -470,9 +470,8 @@ UniValue getdeprecationinfo(const UniValue& params, bool fHelp)
         eos.pushKV("block_height", DEPRECATION_HEIGHT);
         {
             LOCK(cs_main);
-            auto blocksToDeprecation = DEPRECATION_HEIGHT - chainActive.Height();
 
-            eos.pushKV("estimated_time", GetTime() + (blocksToDeprecation * EXPECTED_BLOCKS_PER_HOUR * 60 * 60));
+            eos.pushKV("estimated_time", EstimatedNodeDeprecationTime(*GetNodeClock(), chainActive.Height()));
         }
         obj.pushKV("end_of_service", eos);
     }