diff --git a/app/services/software_update_check_service.rb b/app/services/software_update_check_service.rb
index 2bb2b6efed..8c95ca546e 100644
--- a/app/services/software_update_check_service.rb
+++ b/app/services/software_update_check_service.rb
@@ -34,6 +34,7 @@ class SoftwareUpdateCheckService < BaseService
     if ENV.fetch('UPDATE_CHECK_SOURCE', 'kmyblue') == 'kmyblue'
       @version = "#{Mastodon::Version.kmyblue_major}.#{Mastodon::Version.kmyblue_minor}"
       @version += '-lts' if Setting.check_lts_version_only
+      @version += '-dev' if Mastodon::Version.dev?
     else
       @version = Mastodon::Version.to_s.split('+')[0]
     end
diff --git a/lib/mastodon/version.rb b/lib/mastodon/version.rb
index 007c768cdd..7ca337cd3d 100644
--- a/lib/mastodon/version.rb
+++ b/lib/mastodon/version.rb
@@ -5,7 +5,7 @@ module Mastodon
     module_function
 
     def kmyblue_major
-      10
+      11
     end
 
     def kmyblue_minor
@@ -13,7 +13,9 @@ module Mastodon
     end
 
     def kmyblue_flag
-      nil # 'LTS'
+      # 'LTS'
+      'dev'
+      # nil
     end
 
     def major
@@ -80,6 +82,14 @@ module Mastodon
                        end
     end
 
+    def lts?
+      kmyblue_flag == 'LTS'
+    end
+
+    def dev?
+      kmyblue_flag == 'dev'
+    end
+
     def repository
       ENV.fetch('GITHUB_REPOSITORY', 'kmycode/mastodon')
     end
diff --git a/spec/services/software_update_check_service_spec.rb b/spec/services/software_update_check_service_spec.rb
index 7cc99bb09c..846cbdb709 100644
--- a/spec/services/software_update_check_service_spec.rb
+++ b/spec/services/software_update_check_service_spec.rb
@@ -6,7 +6,7 @@ RSpec.describe SoftwareUpdateCheckService, type: :service do
   subject { described_class.new }
 
   shared_examples 'when the feature is enabled' do
-    let(:full_update_check_url) { "#{update_check_url}?version=#{Mastodon::Version.kmyblue_major}.#{Mastodon::Version.kmyblue_minor}-lts" }
+    let(:full_update_check_url) { "#{update_check_url}?version=#{Mastodon::Version.kmyblue_major}.#{Mastodon::Version.kmyblue_minor}-lts#{Mastodon::Version.dev? ? '-dev' : ''}" }
 
     let(:devops_role)     { Fabricate(:user_role, name: 'DevOps', permissions: UserRole::FLAGS[:view_devops]) }
     let(:owner_user)      { Fabricate(:user, role: UserRole.find_by(name: 'Owner')) }