I think 1) Kuu will change the setlist eventually and you will be included in the final. Tour does end in November, which is the perfect time to sing a wintery song like you OR 2) Kuu thinks that you shouldn't be included in this concert's setlist because it was already a part of THE ARTIST setlist. Personally I think the right answer is option 1. You is so winterish that I wouldn't be surprised if it was saved for that season.
And a acoustic guitar version of Suki de, suki de, suki de sounds great already even just a idea, omg. 8D