Default is a failure of the debtor to meet the terms of the debt obligation. On 08/17 "investors" attempted to make withdrawals. The terms of the BTCST were that principal and interest could be drawn on demand (demand account). Pirate failed to pay out those investors on 08/17. He also failed to make the next regularly scheduled interest payment. Two weeks later he also stated he will not be paying out any interest post-closure. All of those were causes for default. Under any possible definition of the term, BTCST defaulted on 08/17 when it couldn't honor the terms of the "investment". Pirate could have made the terms anything he wanted. He could have indicated that upon demand accounts would be paid in 30 days. Of course doing so would make the scam less attractive. He set the terms and then couldn't meet them.
Try this on for size. Don't make your mortgage payment instead call the bank up and saying you are closing the mortgage. When the bank asks when you will be paying off the balance tell them you are stopping all interest and will pay them when you get the money. Also be sure to let them know you aren't in default until you tell them you are in default. Let me know how it works out.
Pirate admitting default 2 weeks after the fact doesn't change the fact that he was already in default the day he couldn't meet the terms of his obligation to creditors.