Complex sentence: Bad Religion replaced Finestone with Bobby Schayer, then recorded their next album, "Generator", which was already in completed in the spring of 1991, but was forced to delay its release until a year later.
Split into simpler sentences: Bad Religion replaced Finestone with Bobby Schayer, then recorded their next album, "Generator". The album was completed in the spring of 1991, but the band was forced to delay its release until a year later.