Maybe I missed it but what started it?
You haven't missed anything yet. As of this morning they said inspectors are looking at it, but no information is available.
Home insurance is a huge problem in California. Apparently, the state hasn't allowed insurance companies to adjust rates for reinsurance costs, so the big insurers have not been allowing policy holders to renew. Rather than lose money, they are leaving the state. This happened ~ 3 years ago to me with fire prone property in the Sierra foothills in Northern California, and recently to my sister in non-fire prone Santa Paula (near LA). Those are only two examples, but it has been happening on a massive scale state wide. Many people have been forced into the Cal FAIR plan, an extremely expensive, poor coverage option of last resort.
On the NoCal property, the new owner went with the mandatory policy the mortgage holder put on the property when his policy didn't renew. Hard to believe this the cheapest, and actually only option. The Cal FAIR plan was too expensive, and wouldn't cover much, so it was a no go.
An odd coincidence - my sister's house burnt down last month shortly before her policy expired (house electrical fire, not associated with the wildfires). She had been looking, but it appeared the FAIR plan was the only policy available.
When the final tally is in, I'll bet there is a heartbreaking number of uninsured houses that have burned down in the recent fires. That might help start a bloodless coup in California, much like Prop 13 did when people were forced out of their homes with ungodly tax increases.