diff --git a/CHANGELOG.md b/CHANGELOG.md
index e09647f..aaa5b7a 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -7,6 +7,10 @@ and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0
 
 ## Unreleased
 
+## [0.2.0] - 2020-08-18
+### Changed
+- updated aeon-php/calendar dependency to >=0.4.0
+
 ## [0.1.0] - 2020-08-09
 ### First release :tada:
 - initial release
diff --git a/composer.json b/composer.json
index 6ed2fb1..441fae2 100644
--- a/composer.json
+++ b/composer.json
@@ -7,11 +7,11 @@
     "prefer-stable": true,
     "require": {
         "php": ">=7.4.2",
-        "aeon-php/calendar": "^0.3.0"
+        "aeon-php/calendar": ">=0.4.0"
     },
     "require-dev": {
         "phpunit/phpunit": "^9.3",
-        "aeon-php/calendar-holidays": "^0.1.0"
+        "aeon-php/calendar-holidays": ">=0.2.0"
     },
     "license": "MIT",
     "autoload": {
diff --git a/composer.lock b/composer.lock
index 6b03b0e..97d6b47 100644
--- a/composer.lock
+++ b/composer.lock
@@ -4,20 +4,20 @@
         "Read more about it at https://getcomposer.org/doc/01-basic-usage.md#installing-dependencies",
         "This file is @generated automatically"
     ],
-    "content-hash": "68a90c15374df10aac1b58df667e43b4",
+    "content-hash": "fb6b2c7de46a3ec24313b18a7ca11843",
     "packages": [
         {
             "name": "aeon-php/calendar",
-            "version": "0.3.0",
+            "version": "0.4.0",
             "source": {
                 "type": "git",
                 "url": "https://github.com/aeon-php/calendar.git",
-                "reference": "fcf6af31d67439ea23bb56c64a29769028fdf133"
+                "reference": "c082ccd33577bb8a67b6c2218d888fc4907785a4"
             },
             "dist": {
                 "type": "zip",
-                "url": "https://api.github.com/repos/aeon-php/calendar/zipball/fcf6af31d67439ea23bb56c64a29769028fdf133",
-                "reference": "fcf6af31d67439ea23bb56c64a29769028fdf133",
+                "url": "https://api.github.com/repos/aeon-php/calendar/zipball/c082ccd33577bb8a67b6c2218d888fc4907785a4",
+                "reference": "c082ccd33577bb8a67b6c2218d888fc4907785a4",
                 "shasum": ""
             },
             "require": {
@@ -25,7 +25,7 @@
             },
             "require-dev": {
                 "ext-bcmath": "*",
-                "phpunit/phpunit": "^9.1"
+                "phpunit/phpunit": "^9.3"
             },
             "suggest": {
                 "ext-bcmath": "Compare time units with high precision"
@@ -50,32 +50,36 @@
                 "immutable",
                 "time"
             ],
+            "support": {
+                "issues": "https://github.com/aeon-php/calendar/issues",
+                "source": "https://github.com/aeon-php/calendar/tree/0.4.0"
+            },
             "funding": [
                 {
                     "url": "https://github.com/norberttech",
                     "type": "github"
                 }
             ],
-            "time": "2020-08-01T19:24:48+00:00"
+            "time": "2020-08-15T18:07:07+00:00"
         }
     ],
     "packages-dev": [
         {
             "name": "aeon-php/calendar-holidays",
-            "version": "0.1.0",
+            "version": "0.2.0",
             "source": {
                 "type": "git",
                 "url": "https://github.com/aeon-php/calendar-holidays.git",
-                "reference": "9073cb1aa2e8084a9509b68d7283b8464e4276c0"
+                "reference": "bfe0da01d944e9aa608679d229b5e9685b8c28fa"
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             "dist": {
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-                "url": "https://api.github.com/repos/aeon-php/calendar-holidays/zipball/9073cb1aa2e8084a9509b68d7283b8464e4276c0",
-                "reference": "9073cb1aa2e8084a9509b68d7283b8464e4276c0",
+                "url": "https://api.github.com/repos/aeon-php/calendar-holidays/zipball/bfe0da01d944e9aa608679d229b5e9685b8c28fa",
+                "reference": "bfe0da01d944e9aa608679d229b5e9685b8c28fa",
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             },
             "require": {
-                "aeon-php/calendar": "^0.3.0",
+                "aeon-php/calendar": ">=0.4.0",
                 "ext-json": "*",
                 "ext-mbstring": "*",
                 "php": ">=7.4.2"
@@ -108,13 +112,17 @@
                 "immutable",
                 "sleep"
             ],
+            "support": {
+                "issues": "https://github.com/aeon-php/calendar-holidays/issues",
+                "source": "https://github.com/aeon-php/calendar-holidays/tree/1.x"
+            },
             "funding": [
                 {
                     "url": "https://github.com/norberttech",
                     "type": "github"
                 }
             ],
-            "time": "2020-08-09T09:04:53+00:00"
+            "time": "2020-08-18T19:40:40+00:00"
         },
         {
             "name": "doctrine/instantiator",
@@ -298,6 +306,10 @@
                 "parser",
                 "php"
             ],
+            "support": {
+                "issues": "https://github.com/nikic/PHP-Parser/issues",
+                "source": "https://github.com/nikic/PHP-Parser/tree/master"
+            },
             "time": "2020-08-09T10:23:20+00:00"
         },
         {
@@ -354,6 +366,10 @@
                 }
             ],
             "description": "Component for reading phar.io manifest information from a PHP Archive (PHAR)",
+            "support": {
+                "issues": "https://github.com/phar-io/manifest/issues",
+                "source": "https://github.com/phar-io/manifest/tree/master"
+            },
             "time": "2020-06-27T14:33:11+00:00"
         },
         {
@@ -401,6 +417,10 @@
                 }
             ],
             "description": "Library for handling version information and constraints",
+            "support": {
+                "issues": "https://github.com/phar-io/version/issues",
+                "source": "https://github.com/phar-io/version/tree/master"
+            },
             "time": "2020-06-27T14:39:04+00:00"
         },
         {
@@ -458,16 +478,16 @@
         },
         {
             "name": "phpdocumentor/reflection-docblock",
-            "version": "5.2.0",
+            "version": "5.2.1",
             "source": {
                 "type": "git",
                 "url": "https://github.com/phpDocumentor/ReflectionDocBlock.git",
-                "reference": "3170448f5769fe19f456173d833734e0ff1b84df"
+                "reference": "d870572532cd70bc3fab58f2e23ad423c8404c44"
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             "dist": {
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-                "url": "https://api.github.com/repos/phpDocumentor/ReflectionDocBlock/zipball/3170448f5769fe19f456173d833734e0ff1b84df",
-                "reference": "3170448f5769fe19f456173d833734e0ff1b84df",
+                "url": "https://api.github.com/repos/phpDocumentor/ReflectionDocBlock/zipball/d870572532cd70bc3fab58f2e23ad423c8404c44",
+                "reference": "d870572532cd70bc3fab58f2e23ad423c8404c44",
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             },
             "require": {
@@ -506,7 +526,11 @@
                 }
             ],
             "description": "With this component, a library can provide support for annotations via DocBlocks or otherwise retrieve information that is embedded in a DocBlock.",
-            "time": "2020-07-20T20:05:34+00:00"
+            "support": {
+                "issues": "https://github.com/phpDocumentor/ReflectionDocBlock/issues",
+                "source": "https://github.com/phpDocumentor/ReflectionDocBlock/tree/master"
+            },
+            "time": "2020-08-15T11:14:08+00:00"
         },
         {
             "name": "phpdocumentor/type-resolver",
@@ -626,16 +650,16 @@
         },
         {
             "name": "phpunit/php-code-coverage",
-            "version": "9.1.3",
+            "version": "9.1.4",
             "source": {
                 "type": "git",
                 "url": "https://github.com/sebastianbergmann/php-code-coverage.git",
-                "reference": "4abbce3b0ad05f2e7143ea5f775d5513cb5261e4"
+                "reference": "4422fca28c3634e2de8c7c373af97a104dd1a45f"
             },
             "dist": {
                 "type": "zip",
-                "url": "https://api.github.com/repos/sebastianbergmann/php-code-coverage/zipball/4abbce3b0ad05f2e7143ea5f775d5513cb5261e4",
-                "reference": "4abbce3b0ad05f2e7143ea5f775d5513cb5261e4",
+                "url": "https://api.github.com/repos/sebastianbergmann/php-code-coverage/zipball/4422fca28c3634e2de8c7c373af97a104dd1a45f",
+                "reference": "4422fca28c3634e2de8c7c373af97a104dd1a45f",
                 "shasum": ""
             },
             "require": {
@@ -689,13 +713,17 @@
                 "testing",
                 "xunit"
             ],
+            "support": {
+                "issues": "https://github.com/sebastianbergmann/php-code-coverage/issues",
+                "source": "https://github.com/sebastianbergmann/php-code-coverage/tree/master"
+            },
             "funding": [
                 {
                     "url": "https://github.com/sebastianbergmann",
                     "type": "github"
                 }
             ],
-            "time": "2020-08-10T17:45:51+00:00"
+            "time": "2020-08-13T15:04:53+00:00"
         },
         {
             "name": "phpunit/php-file-iterator",
@@ -808,6 +836,10 @@
             "keywords": [
                 "process"
             ],
+            "support": {
+                "issues": "https://github.com/sebastianbergmann/php-invoker/issues",
+                "source": "https://github.com/sebastianbergmann/php-invoker/tree/3.1.0"
+            },
             "funding": [
                 {
                     "url": "https://github.com/sebastianbergmann",
@@ -1020,6 +1052,10 @@
                 "testing",
                 "xunit"
             ],
+            "support": {
+                "issues": "https://github.com/sebastianbergmann/phpunit/issues",
+                "source": "https://github.com/sebastianbergmann/phpunit/tree/9.3"
+            },
             "funding": [
                 {
                     "url": "https://phpunit.de/donate.html",
@@ -1262,6 +1298,10 @@
             ],
             "description": "Library for calculating the complexity of PHP code units",
             "homepage": "https://github.com/sebastianbergmann/complexity",
+            "support": {
+                "issues": "https://github.com/sebastianbergmann/complexity/issues",
+                "source": "https://github.com/sebastianbergmann/complexity/tree/2.0.0"
+            },
             "funding": [
                 {
                     "url": "https://github.com/sebastianbergmann",
@@ -1528,6 +1568,10 @@
             "keywords": [
                 "global state"
             ],
+            "support": {
+                "issues": "https://github.com/sebastianbergmann/global-state/issues",
+                "source": "https://github.com/sebastianbergmann/global-state/tree/5.0.0"
+            },
             "funding": [
                 {
                     "url": "https://github.com/sebastianbergmann",
@@ -1581,6 +1625,10 @@
             ],
             "description": "Library for counting the lines of code in PHP source code",
             "homepage": "https://github.com/sebastianbergmann/lines-of-code",
+            "support": {
+                "issues": "https://github.com/sebastianbergmann/lines-of-code/issues",
+                "source": "https://github.com/sebastianbergmann/lines-of-code/tree/1.0.0"
+            },
             "funding": [
                 {
                     "url": "https://github.com/sebastianbergmann",
@@ -1988,6 +2036,9 @@
                 "polyfill",
                 "portable"
             ],
+            "support": {
+                "source": "https://github.com/symfony/polyfill-ctype/tree/v1.18.0"
+            },
             "funding": [
                 {
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@@ -2117,5 +2168,5 @@
         "php": ">=7.4.2"
     },
     "platform-dev": [],
-    "plugin-api-version": "1.1.0"
+    "plugin-api-version": "2.0.0"
 }