Complex sentence: On February 18th, the band released their first nationally distributed CD, "Progressive", and a month later, on March 26th, they announced that they would be debuting from a major label at their third self-planned event, which also sold out.
Split into simpler sentences: On February 18th, the band released their first nationally distributed CD, "Progressive". A month later, on March 26th, they announced that they would debut from a major label at their third self-planned event, which also sold out.