diff --git a/configs/mainnet.yaml b/configs/mainnet.yaml
index 90e5d8736..be61d070c 100644
--- a/configs/mainnet.yaml
+++ b/configs/mainnet.yaml
@@ -29,7 +29,7 @@ GENESIS_DELAY: 604800
 
 # Altair
 ALTAIR_FORK_VERSION: 0x01000000
-ALTAIR_FORK_EPOCH: 74240  # Oct 27, 2021, 10:56:23pm UTC
+ALTAIR_FORK_EPOCH: 74240  # Oct 27, 2021, 10:56:23am UTC
 # Merge
 MERGE_FORK_VERSION: 0x02000000
 MERGE_FORK_EPOCH: 18446744073709551615