POC for laravel/framework#31778 cover this case

$model = User::query()->firstOrFail();
$carbon = $model->date_time_carbon_casted;
$carbon->addDay();
echo $model->col_with_get_mutator_that_depends_on_date_time_carbon_casted;
// would print 'value date time' without the added day before this commit

Author: Pantea Marius-ciclistu

illuminate/Database/Eloquent/Concerns/HasAttributes.php

@@ -509,18 +509,26 @@ protected function throwMissingAttributeExceptionIfApplicable($key)
      */
     public function getAttributeValue($key)
     {
-        return $this->transformModelValue($key, $this->getAttributeFromArray($key));
+        return $this->transformModelValue($key, $this->getAttributeFromArray($key, true));
     }
 
     /**
      * Get an attribute from the $attributes array without transformation
      * @see self::getAttributeValue
      *
      * @param string $key
+     * @param bool $mergeAllAttributesFromCachedCasts
      * @return mixed
      */
     protected function getAttributeFromArray($key)
     {
+        if (
+            true === (\func_get_args()[1] ?? false)
+            && ($this->hasGetMutator($key) || $this->hasAttributeGetMutator($key))
+        ) {
+            return $this->getAttributes()[$key] ?? null;
+        }
+
         $this->mergeAttributesFromClassCasts($key);
         $this->mergeAttributesFromAttributeCasts($key);