diff --git a/pkg/cannon/deriver/beacon/eth/v2/attester_slashing.go b/pkg/cannon/deriver/beacon/eth/v2/attester_slashing.go
index c54c6613..1b126575 100644
--- a/pkg/cannon/deriver/beacon/eth/v2/attester_slashing.go
+++ b/pkg/cannon/deriver/beacon/eth/v2/attester_slashing.go
@@ -164,7 +164,7 @@ func (a *AttesterSlashingDeriver) lookAheadAtLocations(ctx context.Context, loca
 			return
 		}
 
-		for i := uint64(0); i <= uint64(sp.SlotsPerEpoch); i++ {
+		for i := uint64(0); i <= uint64(sp.SlotsPerEpoch-1); i++ {
 			slot := phase0.Slot(i + uint64(epoch)*uint64(sp.SlotsPerEpoch))
 
 			// Add the block to the preload queue so it's available when we need it
@@ -181,7 +181,7 @@ func (a *AttesterSlashingDeriver) processEpoch(ctx context.Context, epoch phase0
 
 	allEvents := []*xatu.DecoratedEvent{}
 
-	for i := uint64(0); i <= uint64(sp.SlotsPerEpoch); i++ {
+	for i := uint64(0); i <= uint64(sp.SlotsPerEpoch-1); i++ {
 		slot := phase0.Slot(i + uint64(epoch)*uint64(sp.SlotsPerEpoch))
 
 		events, err := a.processSlot(ctx, slot)
diff --git a/pkg/cannon/deriver/beacon/eth/v2/beacon_block.go b/pkg/cannon/deriver/beacon/eth/v2/beacon_block.go
index 544c75d9..cba3e162 100644
--- a/pkg/cannon/deriver/beacon/eth/v2/beacon_block.go
+++ b/pkg/cannon/deriver/beacon/eth/v2/beacon_block.go
@@ -167,7 +167,7 @@ func (b *BeaconBlockDeriver) lookAheadAtLocation(ctx context.Context, locations
 			return
 		}
 
-		for i := uint64(0); i <= uint64(sp.SlotsPerEpoch); i++ {
+		for i := uint64(0); i <= uint64(sp.SlotsPerEpoch-1); i++ {
 			slot := phase0.Slot(i + uint64(epoch)*uint64(sp.SlotsPerEpoch))
 
 			// Add the block to the preload queue so it's available when we need it
@@ -184,7 +184,7 @@ func (b *BeaconBlockDeriver) processEpoch(ctx context.Context, epoch phase0.Epoc
 
 	allEvents := []*xatu.DecoratedEvent{}
 
-	for i := uint64(0); i <= uint64(sp.SlotsPerEpoch); i++ {
+	for i := uint64(0); i <= uint64(sp.SlotsPerEpoch-1); i++ {
 		slot := phase0.Slot(i + uint64(epoch)*uint64(sp.SlotsPerEpoch))
 
 		events, err := b.processSlot(ctx, slot)
@@ -192,6 +192,8 @@ func (b *BeaconBlockDeriver) processEpoch(ctx context.Context, epoch phase0.Epoc
 			return nil, errors.Wrapf(err, "failed to process slot %d", slot)
 		}
 
+		b.log.WithField("slot", slot).WithField("index", i).Debug("Created event from block")
+
 		allEvents = append(allEvents, events...)
 	}
 
diff --git a/pkg/cannon/deriver/beacon/eth/v2/bls_to_execution_change.go b/pkg/cannon/deriver/beacon/eth/v2/bls_to_execution_change.go
index 22ae68c2..677ba471 100644
--- a/pkg/cannon/deriver/beacon/eth/v2/bls_to_execution_change.go
+++ b/pkg/cannon/deriver/beacon/eth/v2/bls_to_execution_change.go
@@ -167,7 +167,7 @@ func (b *BLSToExecutionChangeDeriver) lookAheadAtLocation(ctx context.Context, l
 			return
 		}
 
-		for i := uint64(0); i <= uint64(sp.SlotsPerEpoch); i++ {
+		for i := uint64(0); i <= uint64(sp.SlotsPerEpoch-1); i++ {
 			slot := phase0.Slot(i + uint64(epoch)*uint64(sp.SlotsPerEpoch))
 
 			// Add the block to the preload queue so it's available when we need it
@@ -184,7 +184,7 @@ func (b *BLSToExecutionChangeDeriver) processEpoch(ctx context.Context, epoch ph
 
 	allEvents := []*xatu.DecoratedEvent{}
 
-	for i := uint64(0); i <= uint64(sp.SlotsPerEpoch); i++ {
+	for i := uint64(0); i <= uint64(sp.SlotsPerEpoch-1); i++ {
 		slot := phase0.Slot(i + uint64(epoch)*uint64(sp.SlotsPerEpoch))
 
 		events, err := b.processSlot(ctx, slot)
diff --git a/pkg/cannon/deriver/beacon/eth/v2/deposit.go b/pkg/cannon/deriver/beacon/eth/v2/deposit.go
index d92451cf..bf1e7a13 100644
--- a/pkg/cannon/deriver/beacon/eth/v2/deposit.go
+++ b/pkg/cannon/deriver/beacon/eth/v2/deposit.go
@@ -165,7 +165,7 @@ func (b *DepositDeriver) lookAheadAtLocation(ctx context.Context, locations []*x
 			return
 		}
 
-		for i := uint64(0); i <= uint64(sp.SlotsPerEpoch); i++ {
+		for i := uint64(0); i <= uint64(sp.SlotsPerEpoch-1); i++ {
 			slot := phase0.Slot(i + uint64(epoch)*uint64(sp.SlotsPerEpoch))
 
 			// Add the block to the preload queue so it's available when we need it
@@ -182,7 +182,7 @@ func (b *DepositDeriver) processEpoch(ctx context.Context, epoch phase0.Epoch) (
 
 	allEvents := []*xatu.DecoratedEvent{}
 
-	for i := uint64(0); i <= uint64(sp.SlotsPerEpoch); i++ {
+	for i := uint64(0); i <= uint64(sp.SlotsPerEpoch-1); i++ {
 		slot := phase0.Slot(i + uint64(epoch)*uint64(sp.SlotsPerEpoch))
 
 		events, err := b.processSlot(ctx, slot)
diff --git a/pkg/cannon/deriver/beacon/eth/v2/execution_transaction.go b/pkg/cannon/deriver/beacon/eth/v2/execution_transaction.go
index 4839309f..cdea1478 100644
--- a/pkg/cannon/deriver/beacon/eth/v2/execution_transaction.go
+++ b/pkg/cannon/deriver/beacon/eth/v2/execution_transaction.go
@@ -159,7 +159,7 @@ func (b *ExecutionTransactionDeriver) processEpoch(ctx context.Context, epoch ph
 
 	allEvents := []*xatu.DecoratedEvent{}
 
-	for i := uint64(0); i <= uint64(sp.SlotsPerEpoch); i++ {
+	for i := uint64(0); i <= uint64(sp.SlotsPerEpoch-1); i++ {
 		slot := phase0.Slot(i + uint64(epoch)*uint64(sp.SlotsPerEpoch))
 
 		events, err := b.processSlot(ctx, slot)
@@ -186,7 +186,7 @@ func (b *ExecutionTransactionDeriver) lookAheadAtLocation(ctx context.Context, l
 			return
 		}
 
-		for i := uint64(0); i <= uint64(sp.SlotsPerEpoch); i++ {
+		for i := uint64(0); i <= uint64(sp.SlotsPerEpoch-1); i++ {
 			slot := phase0.Slot(i + uint64(epoch)*uint64(sp.SlotsPerEpoch))
 
 			// Add the block to the preload queue so it's available when we need it
diff --git a/pkg/cannon/deriver/beacon/eth/v2/proposer_slashing.go b/pkg/cannon/deriver/beacon/eth/v2/proposer_slashing.go
index 9b0453cb..3bc1f92c 100644
--- a/pkg/cannon/deriver/beacon/eth/v2/proposer_slashing.go
+++ b/pkg/cannon/deriver/beacon/eth/v2/proposer_slashing.go
@@ -155,7 +155,7 @@ func (b *ProposerSlashingDeriver) processEpoch(ctx context.Context, epoch phase0
 
 	allEvents := []*xatu.DecoratedEvent{}
 
-	for i := uint64(0); i <= uint64(sp.SlotsPerEpoch); i++ {
+	for i := uint64(0); i <= uint64(sp.SlotsPerEpoch-1); i++ {
 		slot := phase0.Slot(i + uint64(epoch)*uint64(sp.SlotsPerEpoch))
 
 		events, err := b.processSlot(ctx, slot)
@@ -259,7 +259,7 @@ func (b *ProposerSlashingDeriver) lookAheadAtLocation(ctx context.Context, locat
 			return
 		}
 
-		for i := uint64(0); i <= uint64(sp.SlotsPerEpoch); i++ {
+		for i := uint64(0); i <= uint64(sp.SlotsPerEpoch-1); i++ {
 			slot := phase0.Slot(i + uint64(epoch)*uint64(sp.SlotsPerEpoch))
 
 			// Add the block to the preload queue so it's available when we need it
diff --git a/pkg/cannon/deriver/beacon/eth/v2/voluntary_exit.go b/pkg/cannon/deriver/beacon/eth/v2/voluntary_exit.go
index 7b7ab072..b2bb1b67 100644
--- a/pkg/cannon/deriver/beacon/eth/v2/voluntary_exit.go
+++ b/pkg/cannon/deriver/beacon/eth/v2/voluntary_exit.go
@@ -165,7 +165,7 @@ func (b *VoluntaryExitDeriver) lookAheadAtLocation(ctx context.Context, location
 			return
 		}
 
-		for i := uint64(0); i <= uint64(sp.SlotsPerEpoch); i++ {
+		for i := uint64(0); i <= uint64(sp.SlotsPerEpoch-1); i++ {
 			slot := phase0.Slot(i + uint64(epoch)*uint64(sp.SlotsPerEpoch))
 
 			// Add the block to the preload queue so it's available when we need it
@@ -182,7 +182,7 @@ func (b *VoluntaryExitDeriver) processEpoch(ctx context.Context, epoch phase0.Ep
 
 	allEvents := []*xatu.DecoratedEvent{}
 
-	for i := uint64(0); i <= uint64(sp.SlotsPerEpoch); i++ {
+	for i := uint64(0); i <= uint64(sp.SlotsPerEpoch-1); i++ {
 		slot := phase0.Slot(i + uint64(epoch)*uint64(sp.SlotsPerEpoch))
 
 		events, err := b.processSlot(ctx, slot)
diff --git a/pkg/cannon/deriver/beacon/eth/v2/withdrawal.go b/pkg/cannon/deriver/beacon/eth/v2/withdrawal.go
index 3885b980..fbbbcdc2 100644
--- a/pkg/cannon/deriver/beacon/eth/v2/withdrawal.go
+++ b/pkg/cannon/deriver/beacon/eth/v2/withdrawal.go
@@ -152,7 +152,7 @@ func (b *WithdrawalDeriver) processEpoch(ctx context.Context, epoch phase0.Epoch
 
 	allEvents := []*xatu.DecoratedEvent{}
 
-	for i := uint64(0); i <= uint64(sp.SlotsPerEpoch); i++ {
+	for i := uint64(0); i <= uint64(sp.SlotsPerEpoch-1); i++ {
 		slot := phase0.Slot(i + uint64(epoch)*uint64(sp.SlotsPerEpoch))
 
 		events, err := b.processSlot(ctx, slot)
@@ -218,7 +218,7 @@ func (b *WithdrawalDeriver) lookAheadAtLocation(ctx context.Context, locations [
 			return
 		}
 
-		for i := uint64(0); i <= uint64(sp.SlotsPerEpoch); i++ {
+		for i := uint64(0); i <= uint64(sp.SlotsPerEpoch-1); i++ {
 			slot := phase0.Slot(i + uint64(epoch)*uint64(sp.SlotsPerEpoch))
 
 			// Add the block to the preload queue so it's available when we need it