hahaha all this noise only because one single post getting a bit viral? Could be anything. Why you attribute all this success to the hashtags? Only because in the insights says that the most of the impressions came from hashtags? This is because they are spreading the early success, but this starts with the high engagement on the post. This means the king is the content, if it cause an intense emotion to the viewers they are engaging with likes, comments, shares, saves and stick retained watching the post. Here is where IG is triggering the virality giving a high score to your post which is using the hashtags to get spread, but if you don't put hashtags you'd be shown through the explore page in the niche your account belongs to. Obviously the hashtags are important and can improve your growth but are not as important as some people believe. Content is the first, engagement is the second and the hashtags are the third. If you still don't believe this is easy to demonstrate, just keep using the same hashtags (or at least the same "method" you used to choose the hashtags for that post) on the next posts. You will see that isn't replicate the same performance. In case that is keeping blowing up is just because your account probably got a great trust score in IG and they are just pushing you up. To confirm that are not your magic hashtag combination give it to some friend account in the same niche and you'll see that is not changing almost anything there. Guys, nothing changed, here in IG, youtube, blogs and everywhere, yesterday, today and tomorrow, THE CONTENT IS AND WILL BE THE KING. Don't give to the hashtags more importance than they have.