diff --git a/bvplan/src/cache.rs b/bvplan/src/cache.rs
index a752608..42693ec 100644
--- a/bvplan/src/cache.rs
+++ b/bvplan/src/cache.rs
@@ -31,7 +31,6 @@ pub mod keys {
     pub const SUBSTITUTIONS_HTML: &str = "substs_html";
 
     pub mod substitutions {
-        use chrono::prelude::*;
         use serde::{Deserialize, Serialize};
 
         use super::*;
@@ -59,13 +58,13 @@ pub mod keys {
         #[derive(Deserialize, Serialize, Debug)]
         pub struct SubstitutionQuery {
             #[serde(rename = "d")]
-            pub date: NaiveDate,
+            pub date: String,
             #[serde(rename = "w")]
             pub week_type: db::models::WeekType,
             #[serde(rename = "q")]
-            pub queried_at: NaiveDateTime,
+            pub queried_at: String,
             #[serde(rename = "i")]
-            pub last_import_time: NaiveDateTime,
+            pub last_import_time: String,
             #[serde(rename = "y")]
             pub schoolyear: String,
             #[serde(rename = "t")]
diff --git a/bvplan/src/worker/get_substitutions.rs b/bvplan/src/worker/get_substitutions.rs
index 823fc9d..f51ed2f 100644
--- a/bvplan/src/worker/get_substitutions.rs
+++ b/bvplan/src/worker/get_substitutions.rs
@@ -288,10 +288,22 @@ fn cache_substitutions(
         .load::<StartEndTime>(db_conn)?;
 
     let query = cache::keys::substitutions::SubstitutionQuery {
-        date,
+        date: format!(
+            "{} {}",
+            date.format("%d.%m.%Y"),
+            match date.weekday() {
+                chrono::Weekday::Mon => "Montag",
+                chrono::Weekday::Tue => "Dienstag",
+                chrono::Weekday::Wed => "Mittwoch",
+                chrono::Weekday::Thu => "Donnerstag",
+                chrono::Weekday::Fri => "Freitag",
+                chrono::Weekday::Sat => "Samstag",
+                chrono::Weekday::Sun => "Sonntag",
+            }
+        ),
         week_type,
-        queried_at,
-        last_import_time,
+        queried_at: queried_at.format("%d.%m.%Y %R").to_string(),
+        last_import_time: last_import_time.format("%d.%m.%Y %R").to_string(),
         schoolyear: "schoolyear".to_string(),
         tenant: "OHG Furtwangen".to_string(),
         substitutions: db::schema::substitutions::table