There were talks of it. It was leaked on twitter since Monday and everyone's been anticipating it since. Also, follow the pattern, it's called a quarterly restock so it's pretty much every 3 months. The last restock was on cyber Monday and it happened at 7pm like the previous restocks.
Honestly if you were waiting for a tweet or an alert on your phone, you would've been too late or at least had a very slim chance. I had a few of the links before the tweet and was able to get lucky on 2 pairs of prelude. When the tweet went live, I immediately opened it up for other preludes and it was already all held in cart. And phone alerts take longer than the live tweet so you would've lucked out regardless.