I don't know what it could be, but I've had something similar to happen to me on another game @ midnight.
It wasn't the game's fault but my internet provider. At midnight I would have reconnect to the internet.
Using youtube is not a great comparison imo. It loads up a few seconds of future content so in case it does lose connection it will still play until it runs out or the internet is reconnected. Do you have another online game you can try to play and see if it happens to it too?
For the past week, my game has been disconnecting on the dot at 2.32pm.
I have tested with add-ons and without and still the same results.
I also had my laptop connected to the same router (as my pc) playing a youtube video and there's no disconnection issue when the clock strikes 2.32pm. The video was playing without interruptions.
Any help appreciated!