Earlier in the movie, which is set on a weekend one of the K3-Nieces said that the K3-concert of K3 is next Saturday. Later Manuel said, that the 'Bengeltjes'-spell K3 are put on to is held for 16 days, which is more than 2 weeks. But the day before the concert he told K3 that this is their last day for getting released from the spell, which would be only 6-7 days after the start of the spell.