When IPv6 is enabled on the PDN router interface, any static routes configured to use the PDN interface name as the next hop do not require the explicit configuration of the link-local address. This is because cellular networks do not require a next hop.
The CLI output below shows an example of a static route configuration on an IPv6-enabled PDN router interface.
*A:DUT# config# router
interface "pdn-itf" pdn
port 1/1/1
ipv6
address 1::1/64
exit
exit
static-route-entry ::/0
next-hop "pdn-itf"
exit
exit
exit