Looks like transit data will have to wait. In short, current Valhalla doesn't find transit routes even if the data are there. I opened the corresponding issue with the commit that broke it for us at https://github.com/valhalla/valhalla/issues/2126 .

In theory, I can cook together something with patches that will resolve that issue with Valhalla. However, as there are other issues preventing building Valhalla at OBS if I use older Valhalla releases, I prefer to wait till the transit problem will get resolved upstream and use the time for something more productive.

To fix it myself will require digging into Valhalla's code - which will take quite some time, I suspect.

So, I suggest we wait and see if the transit routing will get fixed upstream and focus on other projects/issues meanwhile.