Complex sentence: The majority of tour dates were posted in July, with the first leg of the tour being in August, with 16 dates in Canada with support from Struc/tures and Asightforsewneyes.
Split into simpler sentences: The majority of tour dates were posted in July. The first leg of the tour was in August, 16 dates in Canada with support from Struc/tures and Asightforsewneyes.