type cast value before blank check for invalid values

lib/validates_timeliness/conversion.rb

@@ -10,6 +10,8 @@ module ValidatesTimeliness
       when :datetime
         value.to_time.in_time_zone
       end
+    rescue
+      nil
     end
 
     def dummy_time(value)

lib/validates_timeliness/validator.rb

@@ -35,10 +35,10 @@ module ValidatesTimeliness
       raw_value = attribute_raw_value(record, attr_name) || value
       return if (@allow_nil && raw_value.nil?) || (@allow_blank && raw_value.blank?)
 
-      return record.errors.add(attr_name, :"invalid_#{@type}") if value.blank?
-
       value = type_cast(value)
 
+      return record.errors.add(attr_name, :"invalid_#{@type}") if value.blank?
+
       @check_restrictions.each do |restriction|
         begin
           restriction_value = type_cast(evaluate_option_value(options[restriction], record))