diff --git a/aleksis/apps/chronos/models.py b/aleksis/apps/chronos/models.py
index 005227458cd02d0769d2b30d1286565ca27da17e..589cf5c737a72a442a5deb6969dd1499386cc612 100644
--- a/aleksis/apps/chronos/models.py
+++ b/aleksis/apps/chronos/models.py
@@ -17,7 +17,11 @@ from django.utils.functional import classproperty
 from django.utils.translation import gettext_lazy as _
 
 from cache_memoize import cache_memoize
-from calendarweek.django import CalendarWeek, i18n_day_abbrs_lazy, i18n_day_names_lazy
+from calendarweek.django import (
+    CalendarWeek,
+    i18n_day_abbr_choices_lazy,
+    i18n_day_name_choices_lazy,
+)
 from colorfield.fields import ColorField
 from django_global_request.middleware import get_request
 
@@ -125,11 +129,11 @@ class ValidityRange(ExtensibleModel):
 
 
 class TimePeriod(ValidityRangeRelatedExtensibleModel):
-    WEEKDAY_CHOICES = list(enumerate(i18n_day_names_lazy()))
-    WEEKDAY_CHOICES_SHORT = list(enumerate(i18n_day_abbrs_lazy()))
+    WEEKDAY_CHOICES = i18n_day_name_choices_lazy()
+    WEEKDAY_CHOICES_SHORT = i18n_day_abbr_choices_lazy()
 
     weekday = models.PositiveSmallIntegerField(
-        verbose_name=_("Week day"), choices=WEEKDAY_CHOICES
+        verbose_name=_("Week day"), choices=i18n_day_name_choices_lazy()
     )
     period = models.PositiveSmallIntegerField(verbose_name=_("Number of period"))
 
diff --git a/poetry.lock b/poetry.lock
index a2419a994be337000b019def1d2e3e1238f16bdf..3415147b8d4413e571382db9c0ef572f5cde1e81 100644
--- a/poetry.lock
+++ b/poetry.lock
@@ -77,7 +77,7 @@ celery = ["Celery[redis,django] (>=4.4.0,<5.0.0)", "django-celery-results (>=1.1
 type = "git"
 url = "https://edugit.org/AlekSIS/official/AlekSIS"
 reference = "master"
-resolved_reference = "02d63ca24d251f8814ab63ca13701dc23a64e32f"
+resolved_reference = "b0ffe11b4aba777fd650949f83f7fd98011def60"
 
 [[package]]
 name = "appdirs"
@@ -204,7 +204,7 @@ python-versions = "*"
 
 [[package]]
 name = "calendarweek"
-version = "0.4.5"
+version = "0.4.6.post2"
 description = "Utilities for working with calendar weeks in Python and Django"
 category = "main"
 optional = false
@@ -1835,11 +1835,11 @@ python-versions = "*"
 
 [[package]]
 name = "toml"
-version = "0.10.1"
+version = "0.10.2"
 description = "Python Library for Tom's Obvious, Minimal Language"
 category = "main"
 optional = false
-python-versions = "*"
+python-versions = ">=2.6, !=3.0.*, !=3.1.*, !=3.2.*"
 
 [[package]]
 name = "tqdm"
@@ -1929,7 +1929,7 @@ testing = ["pytest (>=3.5,!=3.7.3)", "pytest-checkdocs (>=1.2.3)", "pytest-flake
 [metadata]
 lock-version = "1.1"
 python-versions = "^3.7"
-content-hash = "8bf0d507b46c9b692b7360ff0faa5d9c24b4388ea1c69cdc0a0be9b0979d4119"
+content-hash = "3fc24fc95dd61de945d3fe6bd9713e279c6d8b11be1c833805650011ddba1515"
 
 [metadata.files]
 alabaster = [
@@ -1979,8 +1979,8 @@ bleach = [
     {file = "boolean.py-3.8.tar.gz", hash = "sha256:cc24e20f985d60cd4a3a5a1c0956dd12611159d32a75081dabd0c9ab981acaa4"},
 ]
 calendarweek = [
-    {file = "calendarweek-0.4.5-py3-none-any.whl", hash = "sha256:b35fcc087073969d017cede62a7295bcd714a1304bcb4c4e2b0f23acb0265fb1"},
-    {file = "calendarweek-0.4.5.tar.gz", hash = "sha256:5b1788ca435022f9348fc81a718974e51dd85d080f9aa3dad717df70a1bc6e1f"},
+    {file = "calendarweek-0.4.6.post2-py3-none-any.whl", hash = "sha256:17c95c15694f8ae44cac182d9023e3793fe61c54bcd36bb1aeed6dc497d62a6c"},
+    {file = "calendarweek-0.4.6.post2.tar.gz", hash = "sha256:8ddb18d32e05d8373c5ec14b9acbe99f40e0ef67aac4d74c992c62c5d6057d03"},
 ]
 celery-progress = [
     {file = "celery-progress-0.0.12.tar.gz", hash = "sha256:df61d61ac2b29e51b61a2cbd070d28b69f9f538d31e5f4b8076d9721251d6c59"},
@@ -2000,7 +2000,6 @@ click = [
 ]
 colorama = [
     {file = "colorama-0.4.4-py2.py3-none-any.whl", hash = "sha256:9f47eda37229f68eee03b24b9748937c7dc3868f906e8ba69fbcbdd3bc5dc3e2"},
-    {file = "colorama-0.4.4.tar.gz", hash = "sha256:5941b2b48a20143d2267e95b1c2a7603ce057ee39fd88e7329b0c292aa16869b"},
 ]
 colour = [
     {file = "colour-0.1.5-py2.py3-none-any.whl", hash = "sha256:33f6db9d564fadc16e59921a56999b79571160ce09916303d35346dddc17978c"},
@@ -2303,7 +2302,6 @@ importlib-metadata = [
     {file = "importlib_metadata-2.0.0.tar.gz", hash = "sha256:77a540690e24b0305878c37ffd421785a6f7e53c8b5720d211b211de8d0e95da"},
 ]
 iniconfig = [
-    {file = "iniconfig-1.1.1-py2.py3-none-any.whl", hash = "sha256:011e24c64b7f47f6ebd835bb12a743f2fbe9a26d4cecaa7f53bc4f35ee9da8b3"},
     {file = "iniconfig-1.1.1.tar.gz", hash = "sha256:bc3af051d7d14b2ee5ef9969666def0cd1a000e121eaea580d4a313df4b37f32"},
 ]
 isort = [
@@ -2440,8 +2438,6 @@ pillow = [
     {file = "Pillow-7.2.0-cp38-cp38-manylinux2014_aarch64.whl", hash = "sha256:5e51ee2b8114def244384eda1c82b10e307ad9778dac5c83fb0943775a653cd8"},
     {file = "Pillow-7.2.0-cp38-cp38-win32.whl", hash = "sha256:725aa6cfc66ce2857d585f06e9519a1cc0ef6d13f186ff3447ab6dff0a09bc7f"},
     {file = "Pillow-7.2.0-cp38-cp38-win_amd64.whl", hash = "sha256:a060cf8aa332052df2158e5a119303965be92c3da6f2d93b6878f0ebca80b2f6"},
-    {file = "Pillow-7.2.0-pp36-pypy36_pp73-macosx_10_10_x86_64.whl", hash = "sha256:9c87ef410a58dd54b92424ffd7e28fd2ec65d2f7fc02b76f5e9b2067e355ebf6"},
-    {file = "Pillow-7.2.0-pp36-pypy36_pp73-manylinux2010_x86_64.whl", hash = "sha256:e901964262a56d9ea3c2693df68bc9860b8bdda2b04768821e4c44ae797de117"},
     {file = "Pillow-7.2.0-pp36-pypy36_pp73-win32.whl", hash = "sha256:25930fadde8019f374400f7986e8404c8b781ce519da27792cbe46eabec00c4d"},
     {file = "Pillow-7.2.0.tar.gz", hash = "sha256:97f9e7953a77d5a70f49b9a48da7776dc51e9b738151b22dacf101641594a626"},
 ]
@@ -2496,30 +2492,25 @@ pycryptodome = [
     {file = "pycryptodome-3.9.8-cp35-cp35m-macosx_10_6_intel.whl", hash = "sha256:6276478ada411aca97c0d5104916354b3d740d368407912722bd4d11aa9ee4c2"},
     {file = "pycryptodome-3.9.8-cp35-cp35m-manylinux1_i686.whl", hash = "sha256:54bdedd28476dea8a3cd86cb67c0df1f0e3d71cae8022354b0f879c41a3d27b2"},
     {file = "pycryptodome-3.9.8-cp35-cp35m-manylinux1_x86_64.whl", hash = "sha256:f521178e5a991ffd04182ed08f552daca1affcb826aeda0e1945cd989a9d4345"},
-    {file = "pycryptodome-3.9.8-cp35-cp35m-manylinux2014_aarch64.whl", hash = "sha256:f2e045224074d5664dc9cbabbf4f4d4d46f1ee90f24780e3a9a668fd096ff17f"},
     {file = "pycryptodome-3.9.8-cp35-cp35m-win32.whl", hash = "sha256:a207231a52426de3ff20f5608f0687261a3329d97a036c51f7d4c606a6f30c23"},
     {file = "pycryptodome-3.9.8-cp35-cp35m-win_amd64.whl", hash = "sha256:2b998dc45ef5f4e5cf5248a6edfcd8d8e9fb5e35df8e4259b13a1b10eda7b16b"},
     {file = "pycryptodome-3.9.8-cp36-cp36m-macosx_10_6_intel.whl", hash = "sha256:03d5cca8618620f45fd40f827423f82b86b3a202c8d44108601b0f5f56b04299"},
     {file = "pycryptodome-3.9.8-cp36-cp36m-manylinux1_i686.whl", hash = "sha256:f78a68c2c820e4731e510a2df3eef0322f24fde1781ced970bf497b6c7d92982"},
     {file = "pycryptodome-3.9.8-cp36-cp36m-manylinux1_x86_64.whl", hash = "sha256:132a56abba24e2e06a479d8e5db7a48271a73a215f605017bbd476d31f8e71c1"},
-    {file = "pycryptodome-3.9.8-cp36-cp36m-manylinux2014_aarch64.whl", hash = "sha256:cecbf67e81d6144a50dc615629772859463b2e4f815d0c082fa421db362f040e"},
     {file = "pycryptodome-3.9.8-cp36-cp36m-win32.whl", hash = "sha256:67dcad1b8b201308586a8ca2ffe89df1e4f731d5a4cdd0610cc4ea790351c739"},
     {file = "pycryptodome-3.9.8-cp36-cp36m-win_amd64.whl", hash = "sha256:b56638d58a3a4be13229c6a815cd448f9e3ce40c00880a5398471b42ee86f50e"},
     {file = "pycryptodome-3.9.8-cp37-cp37m-macosx_10_6_intel.whl", hash = "sha256:bec2bcdf7c9ce7f04d718e51887f3b05dc5c1cfaf5d2c2e9065ecddd1b2f6c9a"},
     {file = "pycryptodome-3.9.8-cp37-cp37m-manylinux1_i686.whl", hash = "sha256:abc2e126c9490e58a36a0f83516479e781d83adfb134576a5cbe5c6af2a3e93c"},
     {file = "pycryptodome-3.9.8-cp37-cp37m-manylinux1_x86_64.whl", hash = "sha256:ef39c98d9b8c0736d91937d193653e47c3b19ddf4fc3bccdc5e09aaa4b0c5d21"},
-    {file = "pycryptodome-3.9.8-cp37-cp37m-manylinux2014_aarch64.whl", hash = "sha256:87006cf0d81505408f1ae4f55cf8a5d95a8e029a4793360720ae17c6500f7ecc"},
     {file = "pycryptodome-3.9.8-cp37-cp37m-win32.whl", hash = "sha256:4350a42028240c344ee855f032c7d4ad6ff4f813bfbe7121547b7dc579ecc876"},
     {file = "pycryptodome-3.9.8-cp37-cp37m-win_amd64.whl", hash = "sha256:c8bf40cf6e281a4378e25846924327e728a887e8bf0ee83b2604a0f4b61692e8"},
     {file = "pycryptodome-3.9.8-cp38-cp38-macosx_10_9_x86_64.whl", hash = "sha256:d8074c8448cfd0705dfa71ca333277fce9786d0b9cac75d120545de6253f996a"},
     {file = "pycryptodome-3.9.8-cp38-cp38-manylinux1_i686.whl", hash = "sha256:8063a712fba642f78d3c506b0896846601b6de7f5c3d534e388ad0cc07f5a149"},
     {file = "pycryptodome-3.9.8-cp38-cp38-manylinux1_x86_64.whl", hash = "sha256:dd302b6ae3965afeb5ef1b0d92486f986c0e65183cd7835973f0b593800590e6"},
-    {file = "pycryptodome-3.9.8-cp38-cp38-manylinux2014_aarch64.whl", hash = "sha256:663f8de2b3df2e744d6e1610506e0ea4e213bde906795953c1e82279c169f0a7"},
     {file = "pycryptodome-3.9.8-cp38-cp38-win32.whl", hash = "sha256:02e51e1d5828d58f154896ddfd003e2e7584869c275e5acbe290443575370fba"},
     {file = "pycryptodome-3.9.8-cp38-cp38-win_amd64.whl", hash = "sha256:55eb61aca2c883db770999f50d091ff7c14016f2769ad7bca3d9b75d1d7c1b68"},
     {file = "pycryptodome-3.9.8-cp39-cp39-manylinux1_i686.whl", hash = "sha256:39ef9fb52d6ec7728fce1f1693cb99d60ce302aeebd59bcedea70ca3203fda60"},
     {file = "pycryptodome-3.9.8-cp39-cp39-manylinux1_x86_64.whl", hash = "sha256:de6e1cd75677423ff64712c337521e62e3a7a4fc84caabbd93207752e831a85a"},
-    {file = "pycryptodome-3.9.8-cp39-cp39-manylinux2014_aarch64.whl", hash = "sha256:9f62d21bc693f3d7d444f17ed2ad7a913b4c37c15cd807895d013c39c0517dfd"},
     {file = "pycryptodome-3.9.8.tar.gz", hash = "sha256:0e24171cf01021bc5dc17d6a9d4f33a048f09d62cc3f62541e95ef104588bda4"},
 ]
 pydocstyle = [
@@ -2652,8 +2643,6 @@ restructuredtext-lint = [
     {file = "ruamel.yaml.clib-0.2.2-cp38-cp38-manylinux1_x86_64.whl", hash = "sha256:5254af7d8bdf4d5484c089f929cb7f5bafa59b4f01d4f48adda4be41e6d29f99"},
     {file = "ruamel.yaml.clib-0.2.2-cp38-cp38-win32.whl", hash = "sha256:74161d827407f4db9072011adcfb825b5258a5ccb3d2cd518dd6c9edea9e30f1"},
     {file = "ruamel.yaml.clib-0.2.2-cp38-cp38-win_amd64.whl", hash = "sha256:058a1cc3df2a8aecc12f983a48bda99315cebf55a3b3a5463e37bb599b05727b"},
-    {file = "ruamel.yaml.clib-0.2.2-cp39-cp39-macosx_10_9_x86_64.whl", hash = "sha256:c6ac7e45367b1317e56f1461719c853fd6825226f45b835df7436bb04031fd8a"},
-    {file = "ruamel.yaml.clib-0.2.2-cp39-cp39-manylinux1_x86_64.whl", hash = "sha256:b4b0d31f2052b3f9f9b5327024dc629a253a83d8649d4734ca7f35b60ec3e9e5"},
     {file = "ruamel.yaml.clib-0.2.2.tar.gz", hash = "sha256:2d24bd98af676f4990c4d715bcdc2a60b19c56a3fb3a763164d2d8ca0e806ba7"},
 ]
 rules = [
@@ -2755,8 +2744,8 @@ text-unidecode = [
     {file = "text_unidecode-1.3-py2.py3-none-any.whl", hash = "sha256:1311f10e8b895935241623731c2ba64f4c455287888b18189350b67134a822e8"},
 ]
 toml = [
-    {file = "toml-0.10.1-py2.py3-none-any.whl", hash = "sha256:bda89d5935c2eac546d648028b9901107a595863cb36bae0c73ac804a9b4ce88"},
-    {file = "toml-0.10.1.tar.gz", hash = "sha256:926b612be1e5ce0634a2ca03470f95169cf16f939018233a670519cb4ac58b0f"},
+    {file = "toml-0.10.2-py2.py3-none-any.whl", hash = "sha256:806143ae5bfb6a3c6e736a764057db0e6a0e05e338b5630894a5f779cabb4f9b"},
+    {file = "toml-0.10.2.tar.gz", hash = "sha256:b3bda1d108d5dd99f4a20d24d9c348e91c4db7ab1b749200bded2f839ccbe68f"},
 ]
 tqdm = [
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@@ -2773,28 +2762,19 @@ typed-ast = [
     {file = "typed_ast-1.4.1-cp36-cp36m-macosx_10_9_x86_64.whl", hash = "sha256:269151951236b0f9a6f04015a9004084a5ab0d5f19b57de779f908621e7d8b75"},
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     {file = "typed_ast-1.4.1.tar.gz", hash = "sha256:8c8aaad94455178e3187ab22c8b01a3837f8ee50e09cf31f1ba129eb293ec30b"},
 ]
 typing-extensions = [
diff --git a/pyproject.toml b/pyproject.toml
index 8a31ac89d0a99f2b847a74c80454f9e72143d576..f6ae6b8941a93e3593e7756ddae46362c03666e4 100644
--- a/pyproject.toml
+++ b/pyproject.toml
@@ -26,7 +26,7 @@ classifiers = [
 
 [tool.poetry.dependencies]
 python = "^3.7"
-calendarweek = "^0.4.4"
+calendarweek = "^0.4.6"
 AlekSIS = { git = "https://edugit.org/AlekSIS/official/AlekSIS" }
 
 [tool.poetry.dev-dependencies]