i have come to realize and actually also heard from a couple of YouTubers that something like this happens with youtube quite a few times in the year, i.e random increase in sub counts or the other way around, and then it goes back to normal after a couple of hours, and worst part about this situation is that some big youtubers experienced this but their channel never went back to being the same after, it literally ruined their channel. honestly these glitches sometimes work in favor for some and not so much for others.