Thanks for the replies.

As suggested, I did write the hotel and they were quick in reply, saying that the one-stay on four consecutive reservations (FHR-points-Citi Prestige-FHR) was now noted.

Subsequently, the two "interior" reservations -- the ones whose details I can see on the IHG site -- went from the entry-level room (Superior?) to the next level up (Deluxe?) This would/should happen "naturally" as an Ambassador for the Citi Prestige-booked nights (although it had not happened until I wrote), but need not have happened -- at least not by my reading of T&C -- for the two points nights, so I already see myself as ahead there.

Now I can't see what I am in for the two FHR nights; but since the e-mail I got said we would be in same room across the whole stay, I am assuming that we did not get a "double upgrade" for those nights (one level for Ambassador, and another for FHR). But, as per previous paragraph, they are upgrading for the points nights, so on average it is as if we did get the double upgrade. At least that's what I am telling myself. As ever, hope springs eternal, and I have my fingers secretly crossed that on check in, when someone sees the FHR reservation, they'll kick the whole stay up another level. Hey, I can dream, right?

Btw, at IC Bordeaux the benefit is 85 euros for the spa, so I have asked my wife to time her life accordingly, just as we will at the Madrid hotel where you can't use the benefit for hairdresser but you can for martinis and tapas. You have to adjust in this life.