I would say that as a long time Ambassador, things have changed. In the old days you would see the upgrade added to the booking within a few days of making it. Now, often upgrades simply don't happen and I never see them provided in advance.
Note in new T&C's:
All guaranteed upgrades shall be confirmed at the time of arrival at the hotel and are based on the room type selected at the time of booking.
a. Upgrades may vary from the room type selected at time of booking (bed size/type, smoking/non-smoking, view or accessible/speciality room preferences). No compensation shall be provided where the hotel upgrade is declined by the member based on room type.
There are a huge long list of exceptions where the upgrade need not be granted -
https://www.ihg.com/intercontinental...tes-exclusions
I cannot see the 20,000 points mentioned anywhere.