Quick query - about to pass through 7K TP's this evening once the last of my weekend flights post and I'm wondering how BA communicate with you regarding the GUF/Avios/Joker choice at this threshold?

I'd like to opt for the GUF's and use 1 of them on an itinerary I have booked for next week, so once the choice is communicated, do they take long to post?

Many thanks in advance

Pilot37