In my experience, some properties do make different categories of rooms available but not to the level of Hilton and Marriott's Premium Rooms or Hyatt's Suites. However, I've had success with booking a Standard Award and paying a modest cash upcharge to confirm my room into a higher category at IHG properties in APAC and Europe. I find this no different than the higher points cost Hilton, Marriott and Hyatt charge for better or larger rooms. Even with the cash upcharge, there has been a notable discount for me versus booking such rooms only with cash.
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