Absolutely, this story is bullshit.
If you have a car that can drive 20 km/l which isn't exceptional, you only need a 100l gas tank to be able to drive 2000 km.
To claim to be able to do that is an absolutely non story, any gas car can do that easily with just a slightly bigger tank.
When has anyone ever cared about (total) range of a PHEV/ICE? It'll be a 5min stop for another 600 miles on pretty much every PHEV/ICE out there anyway. It's a pointless metric for that type of vehicle.
Um, did they actually do something impressive or is it just a really big gas tank?
I'm struggling to imagine why anyone would even want 1,300 miles of range in a PHEV. Surely it'd be better to have a smaller tank and more space inside the vehicle.