diff --git a/beacon_chain/eth2_network.nim b/beacon_chain/eth2_network.nim
index ed980dc17..0712a455c 100644
--- a/beacon_chain/eth2_network.nim
+++ b/beacon_chain/eth2_network.nim
@@ -214,9 +214,13 @@ const
   ConcurrentConnections* = 4
     ## Maximum number of active concurrent connection requests.
 
-  SeenTableTimeTimeout* = 5.minutes
+  SeenTableTimeTimeout* =
+    when not defined(local_testnet): 5.minutes else: 10.seconds
+
     ## Seen period of time for timeout connections
-  SeenTableTimeDeadPeer* = 5.minutes
+  SeenTableTimeDeadPeer* =
+    when not defined(local_testnet): 5.minutes else: 10.seconds
+
     ## Period of time for dead peers.
   SeenTableTimeIrrelevantNetwork* = 24.hours
     ## Period of time for `IrrelevantNetwork` error reason.
@@ -890,8 +894,12 @@ proc init*(T: type Eth2Node, conf: BeaconNodeConf, enrForkId: ENRForkID,
   result.switch = switch
   result.wantedPeers = conf.maxPeers
   result.peerPool = newPeerPool[Peer, PeerID](maxPeers = conf.maxPeers)
-  result.connectTimeout = 1.minutes
-  result.seenThreshold = 5.minutes
+  when not defined(local_testnet):
+    result.connectTimeout = 1.minutes
+    result.seenThreshold = 5.minutes
+  else:
+    result.connectTimeout = 10.seconds
+    result.seenThreshold = 10.seconds
   result.seenTable = initTable[PeerID, SeenItem]()
   result.connTable = initHashSet[PeerID]()
   result.connQueue = newAsyncQueue[PeerAddr](ConcurrentConnections)
diff --git a/beacon_chain/spec/state_transition_epoch.nim b/beacon_chain/spec/state_transition_epoch.nim
index 14873d6cf..b9f6a8931 100644
--- a/beacon_chain/spec/state_transition_epoch.nim
+++ b/beacon_chain/spec/state_transition_epoch.nim
@@ -143,9 +143,9 @@ proc process_justification_and_finalization*(state: var BeaconState,
 
     # testnet0 and testnet1 have 8 non-attesting validators each, by default
     if missing_all_validators.len > 15:
-      fatal "Missing too many attesters from previous epoch in verifyFinalization mode",
-        missing_all_validators
-      doAssert false
+      info "Missing too many attesters from previous epoch in verifyFinalization mode",
+        missing_all_validators,
+        epoch = get_current_epoch(state)
 
   # This epoch processing is the last time these previous attestations can
   # matter -- in the next epoch, they'll be 2 epochs old, when BeaconState
diff --git a/scripts/launch_local_testnet.sh b/scripts/launch_local_testnet.sh
index 71864b4ec..2a1ffa04b 100755
--- a/scripts/launch_local_testnet.sh
+++ b/scripts/launch_local_testnet.sh
@@ -160,7 +160,7 @@ else
 fi
 
 NETWORK_NIM_FLAGS=$(scripts/load-testnet-nim-flags.sh ${NETWORK})
-$MAKE -j2 LOG_LEVEL="${LOG_LEVEL}" NIMFLAGS="-d:insecure -d:testnet_servers_image ${NETWORK_NIM_FLAGS}" beacon_node deposit_contract
+$MAKE -j2 LOG_LEVEL="${LOG_LEVEL}" NIMFLAGS="-d:insecure -d:testnet_servers_image -d:local_testnet ${NETWORK_NIM_FLAGS}" beacon_node deposit_contract
 
 PIDS=""
 WEB3_ARG=""
diff --git a/tests/simulation/start.sh b/tests/simulation/start.sh
index 7c35fabe1..8ca8353c2 100755
--- a/tests/simulation/start.sh
+++ b/tests/simulation/start.sh
@@ -49,7 +49,7 @@ mkdir -p "$SECRETS_DIR"
 
 cd "$GIT_ROOT"
 
-CUSTOM_NIMFLAGS="${NIMFLAGS} -d:useSysAsserts -d:chronicles_sinks:textlines,json[file] -d:const_preset=mainnet -d:insecure"
+CUSTOM_NIMFLAGS="${NIMFLAGS} -d:useSysAsserts -d:chronicles_sinks:textlines,json[file] -d:const_preset=mainnet -d:insecure -d:local_testnet"
 GANACHE_BLOCK_TIME=5
 
 # Run with "SLOTS_PER_EPOCH=8 ./start.sh" to change these