preface: never done this before
I submitted a build this morning (v0.0.4) and it just passed the testflight beta review.
However, I've made some huge changes so I submitted a new version just now (v0.0.5). I was under the impression once it'd passed beta review once, I was good to go, but no :(
I was actually going to warn you about that but I thought you perhaps already knew.. yeah, big jumps in versions also triggers it. 12 hours-1 day at the moment for a review.
Yes, I am in the dev discord if you want to share it privately. 0.1-5 is quite a jump, but I know I have a setting where I decide whether it's a significant update or not but might be different for you as we're an Apple partner.