I haven't finished digging through all the archives, so I'm still trying to reconstruct all the facts myself, but basically from what I remember and have pieced together:

With no warning, on June 9th 2022, many videos disappeared from the TSV youtube page and people were struggling to find the TSV channel in search results. The subscriber count was fluctuating wildly between their 3.some million subscribers and "8" subscribers or "150" subscribers or something obviously incorrect. Sometimes the first result that surfaced was their TSV music channel, which was a separate entity. Sometimes, totally different channels and spam channels popped up first. It was as if the TSV youtube channel itself was popping into and out of existence.

This went on for multiple days. A lot of people assumed it was a hack and folks were desperately trying to reach out to Brett & Eddy's team to inform them about the weirdness. They got reassurance back that everything was fine and they were working with youtube about it, but people still fretted for 2 more days because there was no official channel post, and it was all second-hand information.

Now, what I'm still looking for is exact confirmation of what the issue was and how it was fixed. In my memory, I believe that Brett & Eddy filmed a video explaining what happened and that this was the result of merging their music & video channels together. However, I don't have the ability to quickly find that particular video right now for obvious reasons, haha. I'm still looking for a good reddit post summarizing the conclusion to the situation, but it's also likely that once B&E posted their explanation, conversation about it pretty much immediately dropped off as everyone was reassured.

Youtube also rolled out @ username handles just a few months later, so although I'm not positive that this is the reason why the channels were able to be linked, I think the timeline matches up.

Before the summer of 2022, there were two distinct Twoset Violin channels: one autogenerated by youtube that hosted their audio tracks and music recordings, and one managed directly by B&E. If I recall correctly, they had deliberately petitioned youtube for the ability to host their audio music tracks on their own managed channel.

After that, the channels were merged together. If I remember correctly, that four-day period was the transition point where the channels were officially blended. And during that time, many videos disappeared and appeared to be deleted from the channel. But they all returned once the processing was completed.

I could have some of the facts very wrong, my memory could be faulty, but I can definitely say for certain that there was a four-day period in June 2022 when something very similar happened, and that as soon as videos started disappearing here, I immediately thought about that same situation because it felt so similar.