diff --git a/config.py b/config.py
index a7cc381..7139443 100644
--- a/config.py
+++ b/config.py
@@ -4,5 +4,13 @@ TELEGRAM_TOKEN = os.environ.get("SECRETARX_TG_TOKEN", None)
 DB_PATH = "data.db"
 CHROMEDRIVER_PATH = "chromedriver"
 
+INTERVALS = {
+    3600 * 0.5: 30,
+    3600 * 1.0: 60,
+    3600 * 1.5: 150,
+    3600 * 2.0: 300,
+    3600 * 3.0: 1800,
+}
+
 
 assert TELEGRAM_TOKEN
diff --git a/tgbot.py b/tgbot.py
index a05ce7c..9acd630 100644
--- a/tgbot.py
+++ b/tgbot.py
@@ -5,6 +5,7 @@ import time
 from threading import Thread
 import sqlite3
 from xclient import XClient
+import config
 
 
 class TelegramBot:
@@ -52,6 +53,18 @@ class TelegramBot:
         def callback_remove_slot(call):
             self.callback_remove_slot(call)
 
+    def update_user_access_token_callback(self, chat_id):
+        def callback(access_token):
+            with sqlite3.connect(self.db_path) as conn:
+                cursor = conn.cursor()
+                cursor.execute(
+                "UPDATE users SET access_token = ? WHERE chat_id = ?",
+                (access_token, chat_id),
+                )
+                conn.commit()
+
+        return callback
+
     def init_db(self):
         with sqlite3.connect(self.db_path) as conn:
             cursor = conn.cursor()
@@ -61,7 +74,8 @@ class TelegramBot:
                     id INTEGER PRIMARY KEY AUTOINCREMENT,
                     chat_id INTEGER UNIQUE,
                     username TEXT,
-                    password TEXT
+                    password TEXT,
+                    access_token TEXT
                 )
             """)
             conn.commit()
@@ -71,12 +85,13 @@ class TelegramBot:
             with sqlite3.connect(self.db_path) as conn:
                 cursor = conn.cursor()
                 cursor.execute(
-                    "SELECT username, password FROM users WHERE chat_id = ?", (chat_id,)
+                    "SELECT username, password, access_token FROM users WHERE chat_id = ?", (chat_id,)
                 )
                 result = cursor.fetchone()
                 if result:
-                    username, password = result
-                    self.xclients[chat_id] = XClient(username, password)
+                    username, password, access_token = result
+                    self.xclients[chat_id] = XClient(username, password, on_access_token_change=self.update_user_access_token_callback(chat_id))
+                    self.xclients[chat_id].access_token = access_token
                 else:
                     self.xclients[chat_id] = None
 
@@ -410,14 +425,17 @@ class TelegramBot:
         now = datetime.now().replace(tzinfo=timezone.utc)
         time_until_slot = (slot_time - now).total_seconds()
 
-        if time_until_slot < 3600:  # If less than 1 hour
-            return 300  # 5 minutes
-        if time_until_slot < 3600 * 2:  # If less than 2 hour
-            return 600  # 10 minutes
-        if time_until_slot < 3600 * 3:  # If less than 3 hour
-            return 900  # 15 minutes
-        else:
-            return 1800  # 30 minutes
+        intervals = sorted(lambda x: x[0], [(k,v) for k,v in config.INTERVALS.items()])
+
+        last_wait = 1800
+
+        for (threshold, wait) in intervals:
+            if time_until_slot < threshold:
+                return wait
+
+            last_wait = wait
+
+        return last_wait
 
     def poll_periodically(self):
         # Continuously poll the watchlist at dynamically adjusted intervals
diff --git a/xclient.py b/xclient.py
index aff7212..eee83af 100644
--- a/xclient.py
+++ b/xclient.py
@@ -11,11 +11,12 @@ from selenium.webdriver.chrome.service import Service
 
 
 class XClient:
-    def __init__(self, username, password):
+    def __init__(self, username, password, on_access_token_change=lambda x: x):
         self.username = username
         self.password = password
         self.access_token = None
         self.id = -1
+        self.on_access_token_change = on_access_token_change
 
         self.session = requests.Session()
         # Default headers for session that mimicks browser
@@ -280,6 +281,7 @@ class XClient:
 
     def login(self):
         self.access_token = self.fetch_access_token()
+        self.on_access_token_change(self.access_token)
 
     def is_logged_in(self):
         # Send request to 'https://backbone-web-api.production.delft.delcom.nl/auth?cf=0 with access token as bearer, check status code