If it works fine and cash flows then sales force would sell it before shutting it down. PE would love to acquire and milk it (and you).

Honestly though it isn’t that hard to go k8s anymore and self host with Argo etc. You can use ChatGPT to figure it all out. Just go bare minimum commodity VPS and use agnostic code as infrastructure like terraform. Then you can just win from the race to the bottom of cost

We know that it isn't intractable, nor is it particularly difficult. However, our particulars are such that Heroku is a small fraction of our expenses, so it simply feels like an annoying distraction from otherwise focusing purely on opportunities for revenue growth.