diff --git a/app/models/ranked_choice_decision.rb b/app/models/ranked_choice_decision.rb
index c9d32c179c2..3f2fd316bd1 100644
--- a/app/models/ranked_choice_decision.rb
+++ b/app/models/ranked_choice_decision.rb
@@ -51,6 +51,7 @@ class RankedChoiceDecision < ApplicationRecord
 
   validates :decision, inclusion: { in: DECISIONS }
   validates :reason, inclusion: { in: REASONS, allow_nil: true }
+  validates :signup_ranked_choice, presence: { unless: ->(record) { record.decision == "skip_user" } }
 
   private
 
diff --git a/app/presenters/tables/ranked_choice_decisions_table_results_presenter.rb b/app/presenters/tables/ranked_choice_decisions_table_results_presenter.rb
index 2e730cba1e1..0e0f312509b 100644
--- a/app/presenters/tables/ranked_choice_decisions_table_results_presenter.rb
+++ b/app/presenters/tables/ranked_choice_decisions_table_results_presenter.rb
@@ -30,7 +30,7 @@ def generate_csv_cell(decision)
     ilike_column_filter :title, association_name: :event
 
     def generate_csv_cell(decision)
-      decision.event.title
+      decision.event&.title
     end
   end
 
diff --git a/app/services/user_signup_constraints.rb b/app/services/user_signup_constraints.rb
index e3bcabbe5e7..07cd5b5a5be 100644
--- a/app/services/user_signup_constraints.rb
+++ b/app/services/user_signup_constraints.rb
@@ -41,14 +41,14 @@ def at_maximum_signups?
   def concurrent_signups_for_run(run)
     current_signups_including_not_counted.select do |signup|
       other_run = signup.run
-      !other_run.event.can_play_concurrently? && run.overlaps?(other_run)
+      other_run == run || (!other_run.event.can_play_concurrently? && run.overlaps?(other_run))
     end
   end
 
   def concurrent_signup_requests_for_run(run)
     pending_signup_requests_including_not_counted.select do |signup_request|
       other_run = signup_request.target_run
-      !other_run.event.can_play_concurrently? && run.overlaps?(other_run)
+      other_run == run || (!other_run.event.can_play_concurrently? && run.overlaps?(other_run))
     end
   end
 
diff --git a/db/migrate/20260409003354_make_lottery_number_index_deferrable.rb b/db/migrate/20260409003354_make_lottery_number_index_deferrable.rb
new file mode 100644
index 00000000000..6272154d6fd
--- /dev/null
+++ b/db/migrate/20260409003354_make_lottery_number_index_deferrable.rb
@@ -0,0 +1,19 @@
+class MakeLotteryNumberIndexDeferrable < ActiveRecord::Migration[8.1]
+  def up
+    remove_index :user_con_profiles, %i[convention_id lottery_number], unique: true
+    execute <<~SQL
+      ALTER TABLE user_con_profiles
+        ADD CONSTRAINT index_user_con_profiles_on_convention_id_and_lottery_number
+        UNIQUE (convention_id, lottery_number)
+        DEFERRABLE INITIALLY DEFERRED;
+    SQL
+  end
+
+  def down
+    execute <<~SQL
+      ALTER TABLE user_con_profiles
+        DROP CONSTRAINT index_user_con_profiles_on_convention_id_and_lottery_number;
+    SQL
+    add_index :user_con_profiles, %i[convention_id lottery_number], unique: true
+  end
+end
diff --git a/db/structure.sql b/db/structure.sql
index fed09025f77..ea1ac43ee32 100644
--- a/db/structure.sql
+++ b/db/structure.sql
@@ -3742,6 +3742,14 @@ ALTER TABLE ONLY public.forms
     ADD CONSTRAINT forms_pkey PRIMARY KEY (id);
 
 
+--
+-- Name: user_con_profiles index_user_con_profiles_on_convention_id_and_lottery_number; Type: CONSTRAINT; Schema: public; Owner: -
+--
+
+ALTER TABLE ONLY public.user_con_profiles
+    ADD CONSTRAINT index_user_con_profiles_on_convention_id_and_lottery_number UNIQUE (convention_id, lottery_number) DEFERRABLE INITIALLY DEFERRED;
+
+
 --
 -- Name: maximum_event_provided_tickets_overrides maximum_event_provided_tickets_overrides_pkey; Type: CONSTRAINT; Schema: public; Owner: -
 --
@@ -5117,13 +5125,6 @@ CREATE INDEX index_user_activity_alerts_on_convention_id ON public.user_activity
 CREATE INDEX index_user_activity_alerts_on_user_id ON public.user_activity_alerts USING btree (user_id);
 
 
---
--- Name: index_user_con_profiles_on_convention_id_and_lottery_number; Type: INDEX; Schema: public; Owner: -
---
-
-CREATE UNIQUE INDEX index_user_con_profiles_on_convention_id_and_lottery_number ON public.user_con_profiles USING btree (convention_id, lottery_number);
-
-
 --
 -- Name: index_user_con_profiles_on_convention_id_and_user_id; Type: INDEX; Schema: public; Owner: -
 --
@@ -6140,6 +6141,7 @@ ALTER TABLE ONLY public.cms_files_pages
 SET search_path TO "$user", public;
 
 INSERT INTO "schema_migrations" (version) VALUES
+('20260409003354'),
 ('20260321193050'),
 ('20260315200824'),
 ('20260315182359'),