Yi Peng 3 crossed both cables C-Lion 1 and BSC at times matching when they broke

It was crossing right on time for the interruptions, a Russian officer was on board, it slowed down while crossing, no other ships were slowing down in that area during that time (rulingnout headwinds) - it cannot get much clearer. China is now participating in hybrid warfare against Europe (unless they present stronger evidence against this assumption)

Why did they leave AIS on?

Having AIS on is mandatory. I'm sure turning it off would raise even higher warning flags than just leaving it on while doing your shady stuff.

Regardless, there are satellites covering the area, so you wouldn't get rid of being tracked anyways, would just be a bit slower.

Every recreational sailor knows that AIS is "mandatory." It's completely routine to see commercial ships running without it.

> It's completely routine to see commercial ships running without it

I think this depends a lot on the location, as different areas seems to make it different levels of "mandatory". Are you speaking about the Baltic Sea specifically based on experience?

Yes. I spent a pandemic summer sailing the north sea, denmark, sweden with a friend. We sailed much less in the baltic and I admittedly kind of mix the north & baltic in my memory but they are very similar regulatory environments re boats so it would surprise me if it was common in one but not the other.

> they are very similar regulatory environments re boats so it would surprise me if it was common in one but not the other.

One has Russia and their ports, while the other doesn't. So preparedness and military presence certainly is different between the two at least.