Lizie

I think the question revolves more around how do Iberia distinguish between you spending the promotional avios rather than the non promotional avios which are in the same account. I have the same issue with 25,000 avios already in my account before I received 90,000 from the promotion.

I don't know the answer to that I'm afraid although some have suggested it works on a first in first out basis which would mean your original pot of avios unfortunately would be reduced first. I can't see that happening myself but only Iberia could give you an answer. Email is the way to go here I think so you get something back from them in writing, just in case things don't go to plan come 1st December.