That doesn't make much sense. They do lean/JIT manufacturing, so it's unlikely that they have too many iPhone boards. Also, the tooling for a completely new alu unibody size for just selling a few iPhone boards does not make much sense.

This is very clearly targeted at Chromebooks in education, where the iPad is not doing too great:

https://www.businessinsider.com/how-apple-lost-the-k-12-educ...

I was making a joke. I might be uniquely knowledgeable about their manufacturing processes...