diff --git a/configs/mainnet/merge.yaml b/configs/mainnet/merge.yaml
index b9924d71d..b4667f5b5 100644
--- a/configs/mainnet/merge.yaml
+++ b/configs/mainnet/merge.yaml
@@ -3,5 +3,5 @@
 # Fork
 # ---------------------------------------------------------------
 MERGE_FORK_VERSION: 0x02000000
-# TBD
-MERGE_FORK_SLOT: 0
+# TBD, temporarily max uint64 value: 2**64 - 1
+MERGE_FORK_SLOT: 18446744073709551615
diff --git a/configs/mainnet/sharding.yaml b/configs/mainnet/sharding.yaml
index 3051ab024..ab2c3f6f4 100644
--- a/configs/mainnet/sharding.yaml
+++ b/configs/mainnet/sharding.yaml
@@ -3,8 +3,8 @@
 # Fork
 # ---------------------------------------------------------------
 SHARDING_FORK_VERSION: 0x03000000
-# TBD
-SHARDING_FORK_SLOT: 0
+# TBD, temporarily max uint64 value: 2**64 - 1
+SHARDING_FORK_SLOT: 18446744073709551615
 
 
 # Beacon-chain
diff --git a/configs/minimal/merge.yaml b/configs/minimal/merge.yaml
index f36caa832..394595d02 100644
--- a/configs/minimal/merge.yaml
+++ b/configs/minimal/merge.yaml
@@ -3,5 +3,5 @@
 # Fork
 # ---------------------------------------------------------------
 MERGE_FORK_VERSION: 0x02000001
-# TBD
-MERGE_FORK_SLOT: 0
+# TBD, temporarily max uint64 value: 2**64 - 1
+MERGE_FORK_SLOT: 18446744073709551615
diff --git a/configs/minimal/sharding.yaml b/configs/minimal/sharding.yaml
index b9497cb53..f3d70111c 100644
--- a/configs/minimal/sharding.yaml
+++ b/configs/minimal/sharding.yaml
@@ -3,8 +3,8 @@
 # Fork
 # ---------------------------------------------------------------
 SHARDING_FORK_VERSION: 0x03000001
-# TBD
-SHARDING_FORK_SLOT: 0
+# TBD, temporarily max uint64 value: 2**64 - 1
+MERGE_FORK_SLOT: 18446744073709551615
 
 
 # Beacon-chain