[ A windy storm... She recalls Minato saying something about patterns, and there was also a strong wind on the last day of the Obon Festival. RO stays silent as she keeps trying to process various info and tying things together. ]

If my hypothesis is correct, I believe the location where we can retrieve the next ofuda is at the castle. However, I cannot be exactly sure, since there was only one other instance of the pattern happening, but it is a real possibility.