Complex sentence: On 21 June 2010, the airline announced via their website that they had ceased all operations until further notice and eight days later, on 29 June 2010 tt was announced that the airline had gone out of business.
Split into simpler sentences: On 21 June 2010, the airline announced via their website that they had ceased all operations until further notice. It was announced on 29 June 2010 that the airline had gone out of business.