[PIF]

As understand it, both the waiting ships and truck get fined. Those trucks that can access CA ports are also waiting for loads sometimes days. Its not the lack truck drivers so much as CA regulation banning whole fleets of company and independent trucks. Two other factors : Lack of drivers to haul loads shows up in rail yards; at warehouses where lack of people to unload tucks creates backlogs.

The while JIT system is FUBARed

[Fraxinus]

Two other factors : Lack of drivers to haul loads shows up in rail yards; at warehouses where lack of people to unload tucks creates backlogs.
The while JIT system is FUBARedI will add another factor that I think has also mangled the supply chain, I suspect that at least one major nodes inventory management system has collapsed and they have very limited idea of where in their yard (or warehouse) important things are.
I believe that fixing this problem is actually going to require working back from the consumer end finding and fixing bottlenecks, otherwise fixing one bottleneck only plugs the supply chains at the next one.