diff --git a/meilitool/src/upgrade/v1_10.rs b/meilitool/src/upgrade/v1_10.rs
index 99fe104e3..671f4d6d2 100644
--- a/meilitool/src/upgrade/v1_10.rs
+++ b/meilitool/src/upgrade/v1_10.rs
@@ -58,8 +58,8 @@ impl From<v1_9::IndexStats> for IndexStats {
             database_size,
             used_database_size,
             field_distribution,
-            created_at,
-            updated_at,
+            created_at: created_at.0,
+            updated_at: updated_at.0,
         }
     }
 }
@@ -76,6 +76,13 @@ fn update_index_stats(
 ) -> anyhow::Result<()> {
     let ctx = || format!("while updating index stats for index `{index_uid}`");
 
+    let stats: Option<&str> = index_stats
+        .remap_data_type::<Str>()
+        .get(sched_wtxn, &index_uuid)
+        .with_context(ctx)
+        .with_context(|| "While reading value")?;
+    dbg!(stats);
+
     let stats: Option<v1_9::IndexStats> = index_stats
         .remap_data_type::<SerdeJson<v1_9::IndexStats>>()
         .get(sched_wtxn, &index_uuid)
@@ -139,13 +146,13 @@ fn date_round_trip(
     key: &str,
 ) -> anyhow::Result<()> {
     let datetime =
-        db.remap_types::<Str, SerdeJson<v1_9::OffsetDateTime>>().get(wtxn, key).with_context(
-            || format!("could not read `{key}` while updating date format for index `{index_uid}`"),
-        )?;
+        db.remap_types::<Str, SerdeJson<v1_9::LegacyTime>>().get(wtxn, key).with_context(|| {
+            format!("could not read `{key}` while updating date format for index `{index_uid}`")
+        })?;
 
     if let Some(datetime) = datetime {
         db.remap_types::<Str, SerdeJson<self::OffsetDateTime>>()
-            .put(wtxn, key, &self::OffsetDateTime(datetime))
+            .put(wtxn, key, &self::OffsetDateTime(datetime.0))
             .with_context(|| {
                 format!(
                     "could not write `{key}` while updating date format for index `{index_uid}`"
diff --git a/meilitool/src/upgrade/v1_9.rs b/meilitool/src/upgrade/v1_9.rs
index faa2d9814..3e6cfde6c 100644
--- a/meilitool/src/upgrade/v1_9.rs
+++ b/meilitool/src/upgrade/v1_9.rs
@@ -1,4 +1,5 @@
 use serde::{Deserialize, Serialize};
+use time::OffsetDateTime;
 
 pub type FieldDistribution = std::collections::BTreeMap<String, u64>;
 
@@ -21,9 +22,9 @@ pub struct IndexStats {
     /// Association of every field name with the number of times it occurs in the documents.
     pub field_distribution: FieldDistribution,
     /// Creation date of the index.
-    pub created_at: time::OffsetDateTime,
+    pub created_at: LegacyTime,
     /// Date of the last update of the index.
-    pub updated_at: time::OffsetDateTime,
+    pub updated_at: LegacyTime,
 }
 
 #[derive(Debug, Deserialize, Serialize)]
@@ -97,4 +98,9 @@ mod rest {
     }
 }
 
-pub type OffsetDateTime = time::OffsetDateTime;
+// 2024-11-04 13:32:08.48368 +00:00:00
+time::serde::format_description!(legacy_datetime, OffsetDateTime, "[year]-[month]-[day] [hour]:[minute]:[second].[subsecond] [offset_hour sign:mandatory]:[offset_minute]:[offset_second]");
+
+#[derive(Debug, serde::Serialize, serde::Deserialize)]
+#[serde(transparent)]
+pub struct LegacyTime(#[serde(with = "legacy_datetime")] pub OffsetDateTime);