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 it 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. On 29 June 2010, it was announced that the airline had gone out of business.