Many small shops start the "rebajas" before January 7th. If you are interested in something, you can walk in the shop and ask them when the "rebajas" start.

You have to take into consideration that everything on "rebajas" gets sold out very fast. And not always you will be able to find your size. If you have a smaller size or a big size, you will get things in "rebajas" for sure, but if not, I suggest you to buy asap. Sometimes when you go back, that fancy thing you once saw it´s already gone!

Good luck!!!!