From bc209cadabbedbefc31f0a9846cd95d2039b971b Mon Sep 17 00:00:00 2001
From: Justin Traglia <95511699+jtraglia@users.noreply.github.com>
Date: Wed, 23 Jul 2025 08:35:27 -0500
Subject: [PATCH] Use `MinEpochsForDataColumnSidecarsRequest` in
 `WithinDAPeriod` for Fulu (#15522)

* Use MinEpochsForDataColumnSidecarsRequest in WithinDAPeriod for Fulu

* Make fixes

* Add blank line
---
 beacon-chain/blockchain/process_block.go      | 3 +--
 changelog/jtraglia_update-within-da-period.md | 3 +++
 config/params/config.go                       | 6 +++++-
 3 files changed, 9 insertions(+), 3 deletions(-)
 create mode 100644 changelog/jtraglia_update-within-da-period.md

diff --git a/beacon-chain/blockchain/process_block.go b/beacon-chain/blockchain/process_block.go
index c74e5efe67..607633e843 100644
--- a/beacon-chain/blockchain/process_block.go
+++ b/beacon-chain/blockchain/process_block.go
@@ -666,10 +666,9 @@ func (s *Service) areDataColumnsAvailable(
 	root [fieldparams.RootLength]byte,
 	block interfaces.ReadOnlyBeaconBlock,
 ) error {
-	// We are only required to check within MIN_EPOCHS_FOR_BLOB_SIDECARS_REQUESTS
+	// We are only required to check within MIN_EPOCHS_FOR_DATA_COLUMN_SIDECARS_REQUESTS.
 	blockSlot, currentSlot := block.Slot(), s.CurrentSlot()
 	blockEpoch, currentEpoch := slots.ToEpoch(blockSlot), slots.ToEpoch(currentSlot)
-
 	if !params.WithinDAPeriod(blockEpoch, currentEpoch) {
 		return nil
 	}
diff --git a/changelog/jtraglia_update-within-da-period.md b/changelog/jtraglia_update-within-da-period.md
new file mode 100644
index 0000000000..2879a0aa25
--- /dev/null
+++ b/changelog/jtraglia_update-within-da-period.md
@@ -0,0 +1,3 @@
+### Fixed
+
+- Use `MinEpochsForDataColumnSidecarsRequest` in `WithinDAPeriod` when in Fulu
diff --git a/config/params/config.go b/config/params/config.go
index ff777832f4..e05ea531cd 100644
--- a/config/params/config.go
+++ b/config/params/config.go
@@ -498,7 +498,11 @@ func FuluEnabled() bool {
 	return BeaconConfig().FuluForkEpoch < math.MaxUint64
 }
 
-// WithinDAPeriod checks if the block epoch is within MIN_EPOCHS_FOR_BLOB_SIDECARS_REQUESTS of the given current epoch.
+// WithinDAPeriod checks if the block epoch is within the data availability retention period.
 func WithinDAPeriod(block, current primitives.Epoch) bool {
+	if block >= BeaconConfig().FuluForkEpoch {
+		return block+BeaconConfig().MinEpochsForDataColumnSidecarsRequest >= current
+	}
+
 	return block+BeaconConfig().MinEpochsForBlobsSidecarsRequest >= current
 }