When stocks go up quickly, many day traders and short term traders find the stock based on various tools which look for stocks that are "in-play". In other words, a stock that has big moves is found by day traders. As stocks move up fast, and day traders and short term traders arrive, it puts options in play that was unexpected by the option sellers. Many of them are large entities. They may determine that they can save money by shorting such a stock and avoiding losing money on options.
In any case, I've seen this pattern in other stocks that moved up fast. The "pattern" does not mean much about the underlying stock.