Encountered block num collision at block 41812326 due to a fork, witnesses are: [["*","2020-03-20T08:38:03"],["*","2020-03-20T08:38:03"]]
So this is what do we see in steemd logs for a while. A fresh top20 consensus witness, thanks to the , started double producing. Seems like they even don't know how to produce blocks properly. Here is a good post about double producing.
I wonder what happens to the blockchain once the competent witnesses are totally gone and all the blockchain has this kind of witnesses don't even know what they're doing.