It may be a clerical error. It should be pop.
Pops can be used colloquially and it means ''suddenly produces, shows up for concert'' just like something that comes up out of nowhere. There are words like popcorn, pop quiz, etc.
Bueno, consejillo. No digas concierto pop tal cual, di : concierto de música pop. Creo que suena mejor
Slds
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