I'm working on a version 2.0 of an app that's been out for a couple of years. I won't link it from here, because, unlike almost every other software company in the world, we are not interested in MOAR UZERZ. We provide a specific Service to a specific demographic, and they know how to find us, just fine.
This project brings in a lot of AI support. It's made a massive difference. The original project took two years to finish (actually four, but we did a "back to the ol' drawing board reset).
It looks like this may only take a couple more months. I've been working on it for two months, already, and have gotten a significant amount done. The things that will slow it down, will be the usual sand in the gears: team communication overhead. Could stretch things out, quite a bit.