Can anyone help explain a weird jump in downloads on my Podtrac analytics?

I started a podcast this summer and have been using Podtrac for analytics. We have nine episodes out and we're very small - most episodes start to plateau at about 50 downloads, and we get between 0-30 downloads daily. According to Podtrac, over two days last week we got so many downloads our total doubled: 241 downloads on Saturday, and 215 on Sunday. This was across all episodes, but the most recent had the most downloads and the first episode had the least. All downloads came from USA and China (we had never had a download from China up til this point). And all downloads cam from unknown clients, except for one each day, which came from "okhttp". Since then the daily downloads have returned to single digits, although half are still coming from China and most are from unknown clients.

I know these aren't real listeners, but can anyone explain what I'm looking at here? Thanks!