multi: increase min cltv delta to 24

diff --git a/itest/lnd_channel_policy_test.go b/itest/lnd_channel_policy_test.go
index 7a333f0..7def317 100644
--- a/itest/lnd_channel_policy_test.go
+++ b/itest/lnd_channel_policy_test.go
@@ -295,7 +295,7 @@ func testUpdateChannelPolicy(ht *lntest.HarnessTest) {
 	// propagated.
 	baseFee = int64(800)
 	feeRate = int64(123)
-	timeLockDelta = uint32(22)
+	timeLockDelta = uint32(24)
 	maxHtlc *= 2
 	inboundBaseFee := int32(-400)
 	inboundFeeRatePpm := int32(-60)
diff --git a/itest/lnd_htlc_timeout_resolver_test.go b/itest/lnd_htlc_timeout_resolver_test.go
index 25aa0af..2710086 100644
--- a/itest/lnd_htlc_timeout_resolver_test.go
+++ b/itest/lnd_htlc_timeout_resolver_test.go
@@ -14,8 +14,8 @@ import (
 )
 
 const (
-	finalCltvDelta  = routing.MinCLTVDelta // 18.
-	thawHeightDelta = finalCltvDelta * 2   // 36.
+	finalCltvDelta  = routing.MinCLTVDelta // 24.
+	thawHeightDelta = finalCltvDelta * 2   // 48.
 )
 
 // makeRouteHints creates a route hints that will allow Carol to be reached
diff --git a/itest/lnd_route_blinding_test.go b/itest/lnd_route_blinding_test.go
index b6c7f10..3ad1f45 100644
--- a/itest/lnd_route_blinding_test.go
+++ b/itest/lnd_route_blinding_test.go
@@ -352,7 +352,7 @@ func (b *blindedForwardTest) setupNetwork(ctx context.Context,
 	withInterceptor bool) {
 
 	carolArgs := []string{
-		"--bitcoin.timelockdelta=18",
+		"--bitcoin.timelockdelta=24",
 		fmt.Sprintf("--bitcoin.defaultremotedelay=%v", toLocalCSV),
 	}
 	if withInterceptor {
@@ -360,7 +360,7 @@ func (b *blindedForwardTest) setupNetwork(ctx context.Context,
 	}
 
 	daveArgs := []string{
-		"--bitcoin.timelockdelta=18",
+		"--bitcoin.timelockdelta=24",
 		fmt.Sprintf("--bitcoin.defaultremotedelay=%v", toLocalCSV),
 	}
 	cfgs := [][]string{nil, nil, carolArgs, daveArgs}
diff --git a/itest/lnd_sweep_test.go b/itest/lnd_sweep_test.go
index c5bcd3b..3874786 100644
--- a/itest/lnd_sweep_test.go
+++ b/itest/lnd_sweep_test.go
@@ -879,7 +879,7 @@ func testSweepHTLCs(ht *lntest.HarnessTest) {
 	// Before we mine empty blocks to check the RBF behavior, we need to be
 	// aware that Bob's incoming HTLC will expire before his outgoing HTLC
 	// deadline is reached. This happens because the incoming HTLC is sent
-	// onchain at CLTVDelta-BroadcastDelta=18-10=8, which means after 8
+	// onchain at CLTVDelta-BroadcastDelta=24-16=8, which means after 8
 	// blocks are mined, we expect Bob force closes the channel Alice->Bob.
 	blocksTillIncomingSweep := cltvDelta -
 		lncfg.DefaultIncomingBroadcastDelta
diff --git a/lntest/harness.go b/lntest/harness.go
index 4b50257..f3ffc92 100644
--- a/lntest/harness.go
+++ b/lntest/harness.go
@@ -54,15 +54,15 @@ const (
 	// mining blocks.
 	maxBlocksAllowed = 100
 
-	finalCltvDelta  = routing.MinCLTVDelta // 18.
-	thawHeightDelta = finalCltvDelta * 2   // 36.
+	finalCltvDelta  = routing.MinCLTVDelta // 24.
+	thawHeightDelta = finalCltvDelta * 2   // 48.
 )
 
 var (
 	// MaxBlocksMinedPerTest is the maximum number of blocks that we allow
 	// a test to mine. This is an exported global variable so it can be
 	// overwritten by other projects that don't have the same constraints.
-	MaxBlocksMinedPerTest = 50
+	MaxBlocksMinedPerTest = 70
 )
 
 // TestCase defines a test case that's been used in the integration test.
@@ -409,13 +409,13 @@ func (h *HarnessTest) checkAndLimitBlocksMined(startHeight int32) {
 	desc += "1. break test into smaller individual tests, especially if " +
 		"this is a table-drive test.\n" +
 		"2. use smaller CSV via `--bitcoin.defaultremotedelay=1.`\n" +
-		"3. use smaller CLTV via `--bitcoin.timelockdelta=18.`\n" +
+		"3. use smaller CLTV via `--bitcoin.timelockdelta=24.`\n" +
 		"4. remove unnecessary CloseChannel when test ends.\n" +
 		"5. use `CreateSimpleNetwork` for efficient channel creation.\n"
 	h.Log(desc)
 
 	// We enforce that the test should not mine more than
-	// MaxBlocksMinedPerTest (50 by default) blocks, which is more than
+	// MaxBlocksMinedPerTest (70 by default) blocks, which is more than
 	// enough to test a multi hop force close scenario.
 	require.LessOrEqualf(
 		h, int(blocksMined), MaxBlocksMinedPerTest,
diff --git a/sample-lnd.conf b/sample-lnd.conf
index 28f18b3..a487565 100644
--- a/sample-lnd.conf
+++ b/sample-lnd.conf
@@ -1878,7 +1878,7 @@
 ; DefaultIncomingBroadcastDelta set by lnd, otherwise the channel will be force
 ; closed anyway. A warning will be logged on startup if this value is not large
 ; enough to prevent force closes.
-; invoices.holdexpirydelta=12
+; invoices.holdexpirydelta=18
 
 [routing]
 
diff --git a/zpay32/hophint.go b/zpay32/hophint.go
index 07872b0..dd1a2ee 100644
--- a/zpay32/hophint.go
+++ b/zpay32/hophint.go
@@ -12,7 +12,7 @@ const (
 	// We adhere to the recommendation in BOLT 02 for terminal payments.
 	// See also:
 	// https://github.com/lightning/bolts/blob/master/02-peer-protocol.md
-	DefaultAssumedFinalCLTVDelta = 18
+	DefaultAssumedFinalCLTVDelta = 24
 
 	// feeRateParts is the total number of parts used to express fee rates.
 	feeRateParts = 1e6