Given it's already Dec 2th, Jan 3th

is a very short time away and though you might score a newly opened seat if inventory is opened a few days prior to flight departure (assuming AY does this and the flight is not mostly sold), you might want to look at every alternative and close date - flexibility really helps in this kind of situation. ¡Buena suerte! (Good luck!)
Vueling is a LCC, based at Barcelona / El Prat de Llobregat.