FlyerTalk Evangelist
Join Date: Aug 2011
Location: Barcelona, London, on a plane
Programs: BA Silver, TK E+, AA PP, Hyatt Globalist, Marriott LT Plat, Hilton Diamond
Posts: 13,041
As you should know, IHG Rewards Club has no formal policy entitling any elites to Club access. Some hotels are generous. Others aren't. Some can be generous sometimes but not always.
FWIW it doesn't matter whether you book the standard room or "one level below Club". You are confusing the Ambassador policy with Rewards Club policy.
The best advice is to expect nothing and be pleasantly surprised if an upgrade occurs.