Suites are not a guaranteed part of the upgrade process, so you have no leg to stand on. However, the day, time and length of your arrival and stay do have an impact, as well as how often you stay at the property. If often, ask to speak to the GM or some other manager and make your dissatisfaction known, as well as the presence of the competition that you could stay at. However, a 5 day stay at a C/Y at one of their few suites is something highly unlikely to be provided, especially during the business week, as someone likely would be willing to pay for the suite for at least one night, so why should they give it to you when they could maximize a great deal of money from that customer?