diff --git a/src/Carbon/Traits/Localization.php b/src/Carbon/Traits/Localization.php
index c83b0291d..4c09e1a63 100644
--- a/src/Carbon/Traits/Localization.php
+++ b/src/Carbon/Traits/Localization.php
@@ -38,7 +38,6 @@ trait Localization
      */
     protected $localTranslator;
 
-
     /**
      * Options for diffForHumans().
      *
@@ -49,7 +48,6 @@ trait Localization
     /**
      * @deprecated To avoid conflict between different third-party libraries, static setters should not be used.
      *             You should rather use the ->settings() method.
-     *
      * @see settings
      *
      * @param int $humanDiffOptions
@@ -62,7 +60,6 @@ public static function setHumanDiffOptions($humanDiffOptions)
     /**
      * @deprecated To avoid conflict between different third-party libraries, static setters should not be used.
      *             You should rather use the ->settings() method.
-     *
      * @see settings
      *
      * @param int $humanDiffOption
@@ -75,7 +72,6 @@ public static function enableHumanDiffOption($humanDiffOption)
     /**
      * @deprecated To avoid conflict between different third-party libraries, static setters should not be used.
      *             You should rather use the ->settings() method.
-     *
      * @see settings
      *
      * @param int $humanDiffOption
diff --git a/src/Carbon/Traits/Options.php b/src/Carbon/Traits/Options.php
index aaebd75bc..f380e6b3a 100644
--- a/src/Carbon/Traits/Options.php
+++ b/src/Carbon/Traits/Options.php
@@ -11,8 +11,6 @@
 
 namespace Carbon\Traits;
 
-use Carbon\Carbon;
-use Carbon\CarbonImmutable;
 use Carbon\CarbonInterface;
 
 /**
@@ -22,7 +20,7 @@
  *
  * Depends on the following methods:
  *
- * @method static Carbon|CarbonImmutable setTimezone
+ * @method \Carbon\Carbon|\Carbon\CarbonImmutable setTimezone($timezone) Set the timezone
  */
 trait Options
 {
@@ -165,7 +163,6 @@ trait Options
     /**
      * @deprecated To avoid conflict between different third-party libraries, static setters should not be used.
      *             You should rather use the ->settings() method.
-     *
      * @see settings
      *
      * Enable the strict mode (or disable with passing false).
@@ -193,7 +190,6 @@ public static function isStrictModeEnabled()
      *             You should rather use the ->settings() method.
      *             Or you can use method variants: addMonthsWithOverflow/addMonthsNoOverflow, same variants
      *             are available for quarters, years, decade, centuries, millennia (singular and plural forms).
-     *
      * @see settings
      *
      * Indicates if months should be calculated with overflow.
@@ -212,7 +208,6 @@ public static function useMonthsOverflow($monthsOverflow = true)
      *             You should rather use the ->settings() method.
      *             Or you can use method variants: addMonthsWithOverflow/addMonthsNoOverflow, same variants
      *             are available for quarters, years, decade, centuries, millennia (singular and plural forms).
-     *
      * @see settings
      *
      * Reset the month overflow behavior.
@@ -239,7 +234,6 @@ public static function shouldOverflowMonths()
      *             You should rather use the ->settings() method.
      *             Or you can use method variants: addYearsWithOverflow/addYearsNoOverflow, same variants
      *             are available for quarters, years, decade, centuries, millennia (singular and plural forms).
-     *
      * @see settings
      *
      * Indicates if years should be calculated with overflow.
@@ -258,7 +252,6 @@ public static function useYearsOverflow($yearsOverflow = true)
      *             You should rather use the ->settings() method.
      *             Or you can use method variants: addYearsWithOverflow/addYearsNoOverflow, same variants
      *             are available for quarters, years, decade, centuries, millennia (singular and plural forms).
-     *
      * @see settings
      *
      * Reset the month overflow behavior.
diff --git a/src/Carbon/Traits/Units.php b/src/Carbon/Traits/Units.php
index 53b5fb063..e612b38c2 100644
--- a/src/Carbon/Traits/Units.php
+++ b/src/Carbon/Traits/Units.php
@@ -217,7 +217,11 @@ public function addUnit($unit, $value = 1, $overflow = null)
         } elseif ($canOverflow = in_array($unit, [
                 'month',
                 'year',
-            ]) && ($overflow === false || ($overflow === null && !($this->{'local'.($ucUnit = ucfirst($unit).'s').'Overflow'} ?? static::{'shouldOverflow'.$ucUnit}())))) {
+            ]) && ($overflow === false || (
+                $overflow === null &&
+                ($ucUnit = ucfirst($unit).'s') &&
+                !($this->{'local'.$ucUnit.'Overflow'} ?? static::{'shouldOverflow'.$ucUnit}())
+            ))) {
             $day = $date->day;
         }
 
diff --git a/tests/Factory/FactoryTest.php b/tests/Factory/FactoryTest.php
index 1637ceda8..9b528f24b 100644
--- a/tests/Factory/FactoryTest.php
+++ b/tests/Factory/FactoryTest.php
@@ -48,4 +48,3 @@ public function testFactory()
         $this->assertSame('01/01/2018', $factory->parse('2018-01-01')->format('d/m/Y'));
     }
 }
-