server: remove accountability signal experiment period

diff --git a/docs/release-notes/release-notes-0.21.0.md b/docs/release-notes/release-notes-0.21.0.md
index 4e032a3..7196579 100644
--- a/docs/release-notes/release-notes-0.21.0.md
+++ b/docs/release-notes/release-notes-0.21.0.md
@@ -75,6 +75,10 @@
   This applies to both funders and fundees, with the ability to override the
   value during channel opening or acceptance.
 
+* Rename [experimental endorsement signal](https://github.com/lightning/blips/blob/a833e7b49f224e1240b5d669e78fa950160f5a06/blip-0004.md)
+  to [accountable](https://github.com/lightningnetwork/lnd/pull/10367) to match
+  the latest [proposal](https://github.com/lightning/blips/pull/67).
+
 ## RPC Updates
 
 ## lncli Updates
diff --git a/htlcswitch/link.go b/htlcswitch/link.go
index 93bbabb..4dbfa52 100644
--- a/htlcswitch/link.go
+++ b/htlcswitch/link.go
@@ -3346,8 +3346,6 @@ func (l *channelLink) processRemoteAdds(fwdPkg *channeldb.FwdPkg) {
 func (l *channelLink) experimentalAccountability(
 	customUpdateAdd record.CustomSet) fn.Option[byte] {
 
-	// Only relay experimental signal if we are within the experiment
-	// period.
 	if !l.cfg.ShouldFwdExpAccountability() {
 		return fn.None[byte]()
 	}
diff --git a/itest/lnd_experimental_accountability.go b/itest/lnd_experimental_accountability.go
index a636769..30296e7 100644
--- a/itest/lnd_experimental_accountability.go
+++ b/itest/lnd_experimental_accountability.go
@@ -57,18 +57,12 @@ func testAccountability(ht *lntest.HarnessTest, aliceAccountable bool) {
 		FeeLimitMsat:   math.MaxInt64,
 	}
 
-	var expectedValue []byte
-	hasAccountability := lntest.ExperimentalAccountabilityActive()
-
-	if hasAccountability {
-		if aliceAccountable {
-			expectedValue = []byte{lnwire.ExperimentalAccountable}
-			t := uint64(lnwire.ExperimentalAccountableType)
-			sendReq.FirstHopCustomRecords = map[uint64][]byte{
-				t: expectedValue,
-			}
-		} else {
-			expectedValue = []byte{lnwire.ExperimentalUnaccountable}
+	expectedValue := []byte{lnwire.ExperimentalUnaccountable}
+	if aliceAccountable {
+		expectedValue = []byte{lnwire.ExperimentalAccountable}
+		t := uint64(lnwire.ExperimentalAccountableType)
+		sendReq.FirstHopCustomRecords = map[uint64][]byte{
+			t: expectedValue,
 		}
 	}
 
@@ -76,12 +70,11 @@ func testAccountability(ht *lntest.HarnessTest, aliceAccountable bool) {
 
 	// Validate that our signal (positive or zero) propagates until carol
 	// and then is dropped because she has disabled the feature.
-	// When the accountability experiment is not active, no signal is sent.
 	validateAccountableAndResume(
-		ht, bobIntercept, hasAccountability, expectedValue,
+		ht, bobIntercept, true, expectedValue,
 	)
 	validateAccountableAndResume(
-		ht, carolIntercept, hasAccountability, expectedValue,
+		ht, carolIntercept, true, expectedValue,
 	)
 	validateAccountableAndResume(ht, daveIntercept, false, nil)
 
diff --git a/itest/lnd_forward_interceptor_test.go b/itest/lnd_forward_interceptor_test.go
index d45d650..f68042d 100644
--- a/itest/lnd_forward_interceptor_test.go
+++ b/itest/lnd_forward_interceptor_test.go
@@ -432,25 +432,14 @@ func testForwardInterceptorRestart(ht *lntest.HarnessTest) {
 	// We should get another notification about the held HTLC.
 	packet = ht.ReceiveHtlcInterceptor(bobInterceptor)
 
-	// Check the expected number of custom records based on whether the
-	// accountability experiment is still active.
-	expectedLen := 1
-	if lntest.ExperimentalAccountabilityActive() {
-		expectedLen = 2
-	}
-	require.Len(ht, packet.InWireCustomRecords, expectedLen)
+	require.Len(ht, packet.InWireCustomRecords, 2)
 	require.Equal(ht, lntest.CustomRecordsWithUnaccountable(customRecords),
 		packet.InWireCustomRecords)
 
 	// And now we forward the payment at Carol, expecting only an
-	// accountability signal in our incoming custom records (if the experiment
-	// is still active).
+	// accountability signal in our incoming custom records.
 	packet = ht.ReceiveHtlcInterceptor(carolInterceptor)
-	expectedCarolLen := 0
-	if lntest.ExperimentalAccountabilityActive() {
-		expectedCarolLen = 1
-	}
-	require.Len(ht, packet.InWireCustomRecords, expectedCarolLen)
+	require.Len(ht, packet.InWireCustomRecords, 1)
 	err = carolInterceptor.Send(&routerrpc.ForwardHtlcInterceptResponse{
 		IncomingCircuitKey: packet.IncomingCircuitKey,
 		Action:             actionResume,
diff --git a/lntest/utils.go b/lntest/utils.go
index a2c3ea8..9994398 100644
--- a/lntest/utils.go
+++ b/lntest/utils.go
@@ -7,11 +7,9 @@ import (
 	"os"
 	"strconv"
 	"strings"
-	"time"
 
 	"github.com/btcsuite/btcd/btcutil"
 	"github.com/btcsuite/btcd/wire"
-	"github.com/lightningnetwork/lnd"
 	"github.com/lightningnetwork/lnd/input"
 	"github.com/lightningnetwork/lnd/lnrpc"
 	"github.com/lightningnetwork/lnd/lntest/wait"
@@ -290,16 +288,6 @@ func CalcStaticFeeBuffer(c lnrpc.CommitmentType, numHTLCs int) btcutil.Amount {
 // tests.
 func CustomRecordsWithUnaccountable(
 	originalRecords lnwire.CustomRecords) map[uint64][]byte {
-
-	if !ExperimentalAccountabilityActive() {
-		// Return nil if there are no records, to match wire encoding.
-		if len(originalRecords) == 0 {
-			return nil
-		}
-
-		return originalRecords.Copy()
-	}
-
 	return originalRecords.MergedCopy(map[uint64][]byte{
 		uint64(lnwire.ExperimentalAccountableType): {
 			lnwire.ExperimentalUnaccountable,
@@ -307,12 +295,6 @@ func CustomRecordsWithUnaccountable(
 	)
 }
 
-// ExperimentalAccountabilityActive returns true if the experimental accountability
-// window is still open.
-func ExperimentalAccountabilityActive() bool {
-	return time.Now().Before(lnd.AccountabilityExperimentEnd)
-}
-
 // LnrpcOutpointToStr returns a string representation of an lnrpc.OutPoint.
 func LnrpcOutpointToStr(outpoint *lnrpc.OutPoint) string {
 	return fmt.Sprintf("%s:%d", outpoint.TxidStr, outpoint.OutputIndex)
diff --git a/rpcserver.go b/rpcserver.go
index 026b224..29efd15 100644
--- a/rpcserver.go
+++ b/rpcserver.go
@@ -780,13 +780,7 @@ func (r *rpcServer) addDeps(ctx context.Context, s *server,
 			return nil
 		},
 		ShouldSetExpAccountability: func() bool {
-			if s.cfg.ProtocolOptions.NoExpAccountability() {
-				return false
-			}
-
-			return clock.NewDefaultClock().Now().Before(
-				AccountabilityExperimentEnd,
-			)
+			return !s.cfg.ProtocolOptions.NoExpAccountability()
 		},
 	}
 
diff --git a/server.go b/server.go
index ef8abbf..3f7b3e8 100644
--- a/server.go
+++ b/server.go
@@ -139,12 +139,6 @@ var (
 	// TODO(roasbeef): add command line param to modify.
 	MaxFundingAmount = funding.MaxBtcFundingAmount
 
-	// AccountabilityExperimentEnd is the time after which nodes should stop
-	// propagating experimental accountable signals.
-	//
-	// Per blip04: January 1, 2026 12:00:00 AM UTC in unix seconds.
-	AccountabilityExperimentEnd = time.Unix(1767225600, 0)
-
 	// ErrGossiperBan is one of the errors that can be returned when we
 	// attempt to finalize a connection to a remote peer.
 	ErrGossiperBan = errors.New("gossiper has banned remote's key")
@@ -4444,13 +4438,7 @@ func (s *server) peerConnected(conn net.Conn, connReq *connmgr.ConnReq,
 		AuxTrafficShaper:       s.implCfg.TrafficShaper,
 		AuxChannelNegotiator:   s.implCfg.AuxChannelNegotiator,
 		ShouldFwdExpAccountability: func() bool {
-			if s.cfg.ProtocolOptions.NoExpAccountability() {
-				return false
-			}
-
-			return clock.NewDefaultClock().Now().Before(
-				AccountabilityExperimentEnd,
-			)
+			return !s.cfg.ProtocolOptions.NoExpAccountability()
 		},
 		NoDisconnectOnPongFailure: s.cfg.NoDisconnectOnPongFailure,
 	}