Use exception for exceptional cases, and handle them properly in application

season_manager.rb

class SeasonManager
  NoSeason = Class.new(StandardError)

  # actual league that we players are playing, if we are in the right date window
  def self.active
    Season.active
  end

  # in season break, it return next season
  def self.upcoming
    Season.upcoming
  end

  def self.for_ordering
    if active && active.upcoming_round?
      active
    elsif upcoming
      upcoming
    else
      raise SeasonManager::NoSeason.new("we are missing upcoming season, create one in admin")
    end
  end
end

season_tickets_controller.rb

class SeasonTicketsController < ApplicationController
  rescue_from SeasonManager::NoSeason, :with => :no_season_apologize
  
  def create
    @season_ticket = SeasonTicket.new(params[:season_ticket])
    # this call can raise SeasonManager::NoSeason
    @season_ticket.season = SeasonManager.for_ordering
    # ...
  end
  
  def no_season_apologize
    flash[:alert] = t("season_tickets.messages.no_season_apologize.alert")
    redirect_to main_app.profile_path
  end
end