So, against like 90% of all odds, we (I) managed to submit the application to Apple for review at the ripe old time of 21.27 last night.
Events of the day included:
- fighting with appstoreconnect (turns out they just return a 500 if you haven't paid your Apple developer membership)
- legal being over an hour later than our absolute deadline for getting the Terms and Conditions and Privacy Policy
- said T&C's and Privacy Policy being delivered in Word, and having to manually format those for our app (thanks guys, please don't use tables again)
- removing FAQs altogether because "it would have taken too long to make those today" (ticket in Jira for this for ~4 months)
- our app was targeting both iPad and iPhone, so we had to rebuild the app for iPhone only because "we don't have app store images for iPad".

On the bright side, that leaves 3 days next week to get the rest of the backend finished for actual go live on Monday 16th, so long as Apple don't reject the app.

Side note: adding the target-device preference affected the android build somehow? despite the preference being iOS only, and wrapped in a platform="iOS" section.