Complex sentence: This is due to regulations from the Norwegian Football Association when Jerv was promoted to OBOS-ligaen before the 2015 season, and parts of the stadium had to be rebuild to meet requirements.
Split into simpler sentences: This is due to regulations from the Norwegian Football Association when Jerv was promoted to OBOS-ligaen before the 2015 season. Parts of the stadium had to be rebuild to meet requirements.