I opened the same session again this morning (after shutting down the computer last night), and a few weird things happened: first, there was already an automation point (close to) the second beat of bar 83, which was not there yesterday. Second, I could add automation points there or anywhere else…
A few things that might be worth mentioning: I had had a few crashes before yesterday with this session, while editing the bender automation, but they were random. (I would say somewhere between 6 and 10 crashes before yesterday.) Yesterday I could reproduce the crash every time with the steps I gave above.
And at least twice (I think 3 times), although I had no crash, I lost a lot of the automation I had done for the pitch bend in this track. I would save and close Ardour and the next time I opened the session, the automation would be gone. Not for the whole track, but from some point (around bar 83 again) on it would be just gone, and I had to just redo it.
I will now go back to work on it and let you know if anything happens again.