Quite simple, really. Make the account private and tweet every possible death date in a reasonable timeframe. Then, upon the Queen's death, delete the incorrec

Quite simple, really. Make the account private and tweet every possible death date in a reasonable timeframe. Then, upon the Queen's death, delete the incorrect tweets and make the account public. I imagine in a few days this account, having gone viral, will start professing to have knowledge about the future value of some cryptocurrency.