Thanks for the link David. What a very interesting article, there is no doubt that the tremendous increase in light from
AT2018cow was a very powerful and unusual event, far out shining its host galaxy CGCG 137-068 as witnessed by the central image of June 20 2018 in the Sky & Telescope article. It seems there are quite a few theories flying around should be interesting to see what conclusions (if any?) are drawn from further observations.
Here is another link