Total apologies for the delay here.
There are no plans right now to update the book for Phoenix 1.6. Unfortunately the upgrades required (text / code changes) would likely make it a v2 book which would be up to Prag.
Luckily, the number of changes is fairly small in the end. Mostly seems related to the generators + PubSub 2.0 having a different setup. The concepts still apply and all of the functions should work as expected.
Thanks for providing your gen commands here.