I'm an agronomist and we are nearly in December. Not a patch of grass has been laid down, there are still cranes midfield and there's no soil, only mud and rocks. No way they pull out a miracle to have Xavi's preffered grass height and density of Camp Nou by February. Unless they import it from outside farm. In natural environment grass grows at slow rate, temperatures between 13-20 degrees and Catalonian winters as mild as they are, they are still below the threshold. I'm no expert in the following thing - I know every big stadium club utilize artificial lights to stimulate photosynthesis to keep the grass in condition, but heating up the soil for the seed to grow is different thing.
I'll gladly take the big L for this comment, but IMO summer of 2025 is the earliest Camp Nou will be ready for football.