Question: when is the nhl 2018 19 schedule released
[{'answer': 'June 21', 'provenance': [{'wikipedia_id': '55632970', 'title': '2018–19 NHL season', 'start_paragraph_id': 6, 'start_character': 3, 'end_paragraph_id': 6, 'end_character': 10, 'bleu_score': 1.0, 'section': 'Section::::League business.:Salary cap.\n'}]}]