The ending was pretty good overall.
I'm not really surprised that they're leaving it off for now, seeing as there probably isn't that much material to make a full next season.
Though it's implied in the end, seeing how they show the mall and that female policemen that tries to keep it in order, and fails.
I love how the whole thing in the background borders between "holy, that's some bad luck" and "IT'S A CONSPIRACY".
One of the cruisers, American at that, having zombie infection taking over just as they're about to fire the missiles to shoot down nukes? Sounds a little too good to be true, though as life shows, unfortunate, holy-s*** bad luck moments happen like that.
For a minute there, I was convinced we would have a Bolivian Army Ending there in the mansion, and I was glad that the group avoided it. Too bad 'bout Saya's parents, though as it implies, we don't know if they did go down fighting or escaped. Nevertheless, most GAR parents this couple of seasons, you will be missed.
Bonus points for that creepy teacher smashing into that concrete block.