Complex sentence: Having been together for less than a year the band hadn't had the opportunity to stockpile songs and the album suffered as a result, featuring a few tracks that "had to go on there just to make up the numbers" (Burgess again).
Split into simpler sentences: Having been together for less than a year, the band hadn't had the opportunity to stockpile songs. The album suffered as a result, featuring a few tracks that "had to go on there just to make up the numbers" (Burgess again).