Architecture for Contraction
robbyonrails.com
robbyonrails.com
The team size may not get smaller -- but it may disappear entirely, which kind of the only room it has to get smaller! More likely, the actual team size may stay the same, but the experience/skill/initiative level the team exhibits may drop drastically.
Still same stuff.
One thing you don't mention that I do prioritize is keeping dependencies up to date. I'm thinking "if the development team disappears entirely, I want the runway to be as long and affordable as possible for you to figure out what to do about this (likely with some per-hour consultancy support) before the thing dies or will require investment you can't afford to survive."