diff --git a/app/controllers/api/v1/statuses_controller.rb b/app/controllers/api/v1/statuses_controller.rb
index a78012e44..9598104d5 100644
--- a/app/controllers/api/v1/statuses_controller.rb
+++ b/app/controllers/api/v1/statuses_controller.rb
@@ -101,7 +101,7 @@ class Api::V1::StatusesController < Api::BaseController
   end
 
   def set_schedule
-    @scheduled_at = status_params[:scheduled_at]&.to_time || (status_params[:scheduled_in].blank? ? nil : Time.now.utc + status_params[:scheduled_in].to_i.seconds)
+    @scheduled_at = status_params[:scheduled_at]&.to_datetime&.to_time || (status_params[:scheduled_in].blank? ? nil : Time.now.utc + status_params[:scheduled_in].to_i.seconds)
   end
 
   def set_expire
diff --git a/app/services/post_status_service.rb b/app/services/post_status_service.rb
index f8cc1612b..19dc846d2 100644
--- a/app/services/post_status_service.rb
+++ b/app/services/post_status_service.rb
@@ -75,7 +75,7 @@ class PostStatusService < BaseService
     @visibility     = :unlisted if @visibility&.to_sym == :public && @account.silenced?
     @visibility     = :limited if @circle.present?
     @visibility     = :limited if @visibility&.to_sym != :direct && @in_reply_to&.limited_visibility?
-    @scheduled_at   = @options[:scheduled_at].is_a?(Time) ? @options[:scheduled_at] : @options[:scheduled_at]&.to_time
+    @scheduled_at   = @options[:scheduled_at].is_a?(Time) ? @options[:scheduled_at] : @options[:scheduled_at]&.to_datetime&.to_time
     @scheduled_at   = nil if scheduled_in_the_past?
     if @quote_id.nil? && md = @text.match(/QT:\s*\[\s*(https:\/\/.+?)\s*\]/)
       @quote_id = quote_from_url(md[1])&.id
@@ -152,7 +152,7 @@ class PostStatusService < BaseService
     @expires_at = @options[:expires_at].is_a?(Time) ? @options[:expires_at] : @options[:expires_at]&.to_time
 
     raise Mastodon::ValidationError, I18n.t('status_expire.validations.invalid_expire_at') if @expires_at.nil?
-    raise Mastodon::ValidationError, I18n.t('status_expire.validations.expire_in_the_past') if @expires_at <= (@options[:scheduled_at]&.to_time || Time.now.utc) + MIN_EXPIRE_OFFSET
+    raise Mastodon::ValidationError, I18n.t('status_expire.validations.expire_in_the_past') if @expires_at <= (@options[:scheduled_at]&.to_datetime&.to_time || Time.now.utc) + MIN_EXPIRE_OFFSET
 
     @expires_action = begin
       case @options[:expires_action]&.to_sym