diff --git a/Changelog.md b/Changelog.md
index 89b508d102..71ec065ccc 100644
--- a/Changelog.md
+++ b/Changelog.md
@@ -5,6 +5,7 @@ Bug Fixes:
 
 * Remove warning when calling `driven_by` in system specs. (Aubin Lorieux, #2302)
 * Fix comparison of times for `#at` in job matchers. (Jon Rowe, Markus Doits, #2304)
+* Fix when using a mailer with `delivery_job` set to a sub class of `ActionMailer::DeliveryJob`
 
 ### 4.0.0 / 2020-03-24
 [Full Changelog](https://github.com/rspec/rspec-rails/compare/v3.9.1...v4.0.0)
diff --git a/spec/rspec/rails/matchers/have_enqueued_mail_spec.rb b/spec/rspec/rails/matchers/have_enqueued_mail_spec.rb
index 938b05f520..152e02fffc 100644
--- a/spec/rspec/rails/matchers/have_enqueued_mail_spec.rb
+++ b/spec/rspec/rails/matchers/have_enqueued_mail_spec.rb
@@ -407,7 +407,7 @@ def self.name; "NonMailerJob"; end
         )
       end
 
-      it "passes when using a mailer with `delivery_job` set to a sub class of `ActionMailer::Base`" do
+      it "passes when using a mailer with `delivery_job` set to a sub class of `ActionMailer::DeliveryJob`" do
         expect {
           UnifiedMailerWithDeliveryJobSubClass.test_email.deliver_later
         }.to have_enqueued_mail(UnifiedMailerWithDeliveryJobSubClass, :test_email)