I found this IHG Straight to Diamond promo in one of the Facebook groups I joined.
Get IHG Diamond status just by registering below and using code 70027
Direct link: https://www.ihg.com/rewardsclub/us/en/offers/promoreg/
You will automatically get IHG Diamond until 12/31/2022, stay 10 or more nights before 12/31/2022 and you can get the Diamond status until 12/31/2023.
IHG Diamond is a top-tier level that can get you complimentary breakfast, and more benefits:
https://www.ihg.com/content/us/en/customer-care/member-tc/2n…
Also had bookings denied perks for being booked through third parties, but I was still put on an Elite floor with a business conference centre and function room that had all-day continental pastries, snacks and drinks, and complimentary wine tastings in the evenings. So you win some, you lose(?) some.