No point in speculating starbuck - only the Ed can ban permanently, and Ed has said several times that he doesn't discuss these matters with the rest of us.
I was surprised too- I don't recall bibblebub ever being controversial or rude. He/she was a very helpful contributor to Q&P.
Yes he openly reappeared as spodocommodo.
It must just be just a coincidence but I notice that after bibblebub disappeared Jumbuck has reappeared on Crosswords this week after an absence of 6 months