'Scuse the delay!
The regs apply to "new safety requirements for air shipment of lithium batteries and associated equipment". 'Air shipment' would apply equally to accompanied baggage and to unaccompanied baggage. Carriers are notoriously lax at interpreting and applying new regs - or they just go moggy, taking the reg out of context and mis-applying them.
After the debacle with the Dream Liner, things are about to get even tighter. At least one of the incidents was with battery in the 'rest' mode; others while charging/discharging.
Scary stuff ...