I took some time during the lockdown to see if I could learn how to build and publish my first Shopify app (Product recommendations local). I used the 'Build a Shopify app with Node and React' guide to get going.
Glancing back over my commit messages and some other notes I took I saw that I had built up a few valuable tips on my experience with the review process, which I ended up going back and forth with about 3 times in the end. It's a bit like your practical driving test!
I've put those notes into a readable post and published it here, hopefully it can be of help to others: https://www.productrecommendationlocal.com/blog/how-we-passed-the-shopify-app-review-process