I don’t know their exact reason for why now, that strike, etc. but it’s common for funds to hedge ahead of time (they did the last round 1-2 days before the adcom announcement, but it seems they won’t make money on them anyway since it seems like the $15 strike won’t be in the money hopefully).
Like JL said, even for believers it’s a cheap way to make sure you don’t lose your shirt on the downside.
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