Just so everyone is aware. The same thing will happen with the 12.9. This isn’t model specific. Apps will be updated over time so I think it’s overblown, but good for people to know.
Why? Hasn’t the 12.9 kept its old aspect ratio?
I’m going by what Steve Troughton Smith is saying. I’m not sure exactly why, but it could be because of the swipe bar or whatever you call it at the bottom. Apps will need to be recompiled in Xcode 10.1.
That could be it. That and the bar at the bottom of the screen taking up space. Either way, apps will need to be recompiled in Xcode 10.1, just like they will for the 11 inch.
What Steve T-S is referring to will happen on both models - essentially because of the home indicator (bar for swiping up to dock/home screen). Apps that are yet to be optimized will have a very thing black space along the bottom where the home indicator is. Other issue is if using split view and only 1 app isn't optimized, they'll both be treated in the old manner with the thin black bar right across the bottom.
Separate from the 11" having the new AR, but still good to be aware of.