there was iPhone 6s zerolution plan, but before iPhone 7 lunch they take out the offer for 6s zerolution. maybe marketing strategy for maxisone with 2 years plan.on the December last year they offer only 16gb 6s/6s+ for zerolution plan, and they offer for all variant storage size on February if not mistaken.... u can google it and u will find it posted in blog and website about iPhone zerolution. you don't see in their website it doesn't mean it was never offered before.

during iPhone 6s they only offered 16GB in early zerolution for iPhone. this time they only offered iPhone 7. maybe need to wait for afew month more for them to offered 7 plus