diff --git a/__init__.py b/__init__.py
index b0a6964..c8ec94f 100644
--- a/__init__.py
+++ b/__init__.py
@@ -14,7 +14,7 @@ class WordDumbDumb(InterfaceActionBase):
     supported_platforms = ["linux", "osx", "windows"]
     author = "xxyzz"
     version = VERSION
-    minimum_calibre_version = (6, 27, 0)
+    minimum_calibre_version = (7, 1, 0)
     actual_plugin = "calibre_plugins.worddumb.ui:WordDumb"
 
     def is_customizable(self):
diff --git a/docs/installation.rst b/docs/installation.rst
index ec03f44..73edfa7 100644
--- a/docs/installation.rst
+++ b/docs/installation.rst
@@ -1,7 +1,7 @@
 Installation
 ============
 
-Install calibre 6.9.0+
+Install calibre 7.1.0+
 ----------------------
 
 - Arch Linux:
@@ -35,7 +35,7 @@ Use `Chocolatey <https://chocolatey.org>`_ or download from https://calibre-eboo
 
    # choco install calibre
 
-Install Python 3.10+ and pip
+Install Python 3.11+ and pip
 ----------------------------
 
 - Arch Linux:
diff --git a/error_dialogs.py b/error_dialogs.py
index 64ef026..594b08c 100644
--- a/error_dialogs.py
+++ b/error_dialogs.py
@@ -3,7 +3,7 @@
 
 GITHUB_URL = "https://github.com/xxyzz/WordDumb"
 INSTALL_PYTHON_DOC = (
-    "https://xxyzz.github.io/WordDumb/installation.html#install-python-3-10-and-pip"
+    "https://xxyzz.github.io/WordDumb/installation.html#install-python-3-11-and-pip"
 )
 
 load_translations()  # type: ignore
diff --git a/interval.py b/interval.py
index 1519491..548f30c 100644
--- a/interval.py
+++ b/interval.py
@@ -41,7 +41,7 @@ def insert(self, node: Node | None, interval: Interval) -> Node:
 
         return node
 
-    def insert_intervals(self, intervals: Interval) -> None:
+    def insert_intervals(self, intervals: list[Interval]) -> None:
         for interval in intervals:
             self.insert(self.root, interval)
 
diff --git a/mediawiki.py b/mediawiki.py
index 31eae4c..7084bef 100644
--- a/mediawiki.py
+++ b/mediawiki.py
@@ -2,7 +2,7 @@
 
 import sqlite3
 from collections import defaultdict
-from datetime import datetime
+from datetime import datetime, timezone
 from functools import partial
 from pathlib import Path
 from typing import TypedDict
@@ -483,16 +483,13 @@ def query(self, items: list[str]) -> None:
 
 
 def inception_text(inception_str: str) -> str:
-    # don't need to remove the last "Z" in Python 3.11
-    inception_str = inception_str.removesuffix("Z")
     if inception_str.startswith("-"):
         bc = int(inception_str[1:5]) + 1  # 2BC: -0001, 1BC: +0000, 1AD: 0001
         years = datetime.now().year + bc
         return f"Inception: {bc} BC({years} years ago)"
     else:
         inception = datetime.fromisoformat(inception_str)
-        # Python 3.11: datetime.now(timezone.utc) - inception
-        years = (datetime.now() - inception).days // 365
+        years = (datetime.now(timezone.utc) - inception).days // 365
         return (
             f"Inception: {inception.strftime('%d %B %Y').lstrip('0')}"
             f"({years} years ago)"