It probably wasn't arranged prior, maybe they didn't realize the huge demand.
How could they not? Whoever booked it should know how great the demand was last time.I hope a 2nd show for Belgium is planned, because I see it selling out quicker than any date this tour has.
If she wants to do another Amsterdam show, it will be after the current Europe dates, there is no gap.
She could add another date there, Stockholm and maybe add a few more dates that she didn't announce yet like Norway. She sold like 21k there last time.