Maybe, maybe not. Perhaps they'll do a very minor update this year, keeping Broadwell but lowering the price, and then keep it around until they can feasibly lower the cost of the MacBook.Even if they update it to this new model this year?
I'm predicting that in 2019 they will have a quad-core MacBook or two, but perhaps they'll keep an entry level dual-core model in the lineup at a lower price. That would kill two birds with one stone: 1) Significantly increase the speed of the MacBook to justify the premium pricing. 2) Have a lower end model to entice buyers at a lower price point.