diff --git a/eth2_libp2p b/eth2_libp2p
index cd94317..1b3ffc3 160000
--- a/eth2_libp2p
+++ b/eth2_libp2p
@@ -1 +1 @@
-Subproject commit cd94317bcf623e7f501cfd5370423bd95fdaff65
+Subproject commit 1b3ffc3e83600da66b54167c37902ab10150c786
diff --git a/helper_functions/src/misc.rs b/helper_functions/src/misc.rs
index a730d93..43b79a8 100644
--- a/helper_functions/src/misc.rs
+++ b/helper_functions/src/misc.rs
@@ -204,7 +204,7 @@ pub fn compute_subnet_for_attestation<P: Preset>(
 
 /// [`compute_subnet_for_blob_sidecar`](https://github.com/ethereum/consensus-specs/blob/v1.4.0-beta.1/specs/deneb/validator.md#sidecar)
 #[must_use]
-pub const fn compute_subnet_for_blob_sidecar(config: &Config, blob_index: BlobIndex) -> SubnetId {
+pub fn compute_subnet_for_blob_sidecar(config: &Config, blob_index: BlobIndex) -> SubnetId {
     blob_index % config.blob_sidecar_subnet_count
 }
 
diff --git a/types/src/combined.rs b/types/src/combined.rs
index 37e6881..e8dc200 100644
--- a/types/src/combined.rs
+++ b/types/src/combined.rs
@@ -1248,9 +1248,8 @@ impl<P: Preset> SszWrite for LightClientUpdate<P> {
     fn write_variable(&self, bytes: &mut Vec<u8>) -> Result<(), WriteError> {
         match self {
             Self::Altair(update) => {
-                let size = AltairLightClientUpdate::<P>::SIZE.get();
                 let length_before = bytes.len();
-                let length_after = length_before + size;
+                let length_after = length_before + AltairLightClientUpdate::<P>::SIZE.get();
 
                 bytes.resize(length_after, 0);
                 update.write_fixed(&mut bytes[length_before..]);
diff --git a/types/src/config.rs b/types/src/config.rs
index 383e882..4e094ab 100644
--- a/types/src/config.rs
+++ b/types/src/config.rs
@@ -136,7 +136,7 @@ pub struct Config {
     #[serde(with = "serde_utils::string_or_native")]
     pub min_epochs_for_blob_sidecars_requests: u64,
     #[serde(with = "serde_utils::string_or_native")]
-    pub blob_sidecar_subnet_count: u64,
+    pub blob_sidecar_subnet_count: NonZeroU64,
     #[serde(with = "serde_utils::string_or_native")]
     pub data_column_sidecar_subnet_count: u64,
 
@@ -232,7 +232,7 @@ impl Default for Config {
             max_request_blocks_deneb: 128,
             max_request_blob_sidecars: 768,
             min_epochs_for_blob_sidecars_requests: 4096,
-            blob_sidecar_subnet_count: 6,
+            blob_sidecar_subnet_count: nonzero!(6_u64),
             data_column_sidecar_subnet_count: 64,
 
             // Transition