Amazon is already running a restaurant food delivery pilot in Seattle, and they already have amazon fresh plus whole foods in stock.

All the "hard" infrastructure is in place, the last thing left for amazon is to create the app/website and market it.

Amazon already offers subscription-less premium mealkits via a partnership with Martha Stewart/Marley Spoon [1] and more affordable options via their Tyson Tastemakers partnership [2].

[1] https://www.amazon.com/b?ie=UTF8&node=14828691011

[2] https://www.amazon.com/b?ie=UTF8&node=16207550011

It might be more like a couple months.

Amazon is a logistics company that nails delivery in volumes Blue Apron cannot even fathom and Whole Foods adds pipelines for ingredient acquisition and physical locations in exactly the places where Blue Apron clients live.